Ubuntu Manpage: podman-create - Create a new container

Provided by: podman_5.0.3+ds1-5ubuntu1_amd64

NAME

       podman-create - Create a new container

SYNOPSIS

       podman create [options] image [command [arg ...]]

       podman container create [options] image [command [arg ...]]

DESCRIPTION

       Creates  a  writable  container layer over the specified image and prepares it for running
       the specified command. The container ID is then printed to  STDOUT.  This  is  similar  to
       podman  run  -d  except  the  container  is  never started. Use the podman start container
       command to start the container at any point.

       The initial status of the container created with podman create is 'created'.

       Default settings for flags are  defined  in  containers.conf.  Most  settings  for  remote
       connections use the server's containers.conf, except when documented in man pages.

IMAGE

The image is specified using transport:path format. If no transport is specified, the
docker (container registry) transport is used by default. For remote Podman, including Mac
and Windows (excluding WSL2) machines, docker is the only allowed transport.

dir:path
An existing local directory path storing the manifest, layer tarballs and signatures as
individual files. This is a non-standardized format, primarily useful for debugging or
noninvasive container inspection.

$ podman save --format docker-dir fedora -o /tmp/fedora
$ podman create dir:/tmp/fedora echo hello

docker://docker-reference (Default)
An image reference stored in a remote container image registry. Example:
"quay.io/podman/stable:latest". The reference can include a path to a specific registry;
if it does not, the registries listed in registries.conf is queried to find a matching
image. By default, credentials from podman login (stored at
$XDG_RUNTIME_DIR/containers/auth.json by default) is used to authenticate; otherwise it
falls back to using credentials in $HOME/.docker/config.json.

$ podman create registry.fedoraproject.org/fedora:latest echo hello

docker-archive:path[:docker-reference] An image stored in the docker save formatted file.
docker-reference is only used when creating such a file, and it must not contain a digest.

$ podman save --format docker-archive fedora -o /tmp/fedora
$ podman create docker-archive:/tmp/fedora echo hello

docker-daemon:docker-reference
An image in docker-reference format stored in the docker daemon internal storage. The
docker-reference can also be an image ID (docker-daemon:algo:digest).

$ sudo docker pull fedora
$ sudo podman create docker-daemon:docker.io/library/fedora echo hello

oci-archive:path:tag
An image in a directory compliant with the "Open Container Image Layout Specification"
at the specified path and specified with a tag.

$ podman save --format oci-archive fedora -o /tmp/fedora
$ podman create oci-archive:/tmp/fedora echo hello

OPTIONS

--add-host=host:ip
Add a custom host-to-IP mapping (host:ip)

Add a line to /etc/hosts. The format is hostname:ip. The --add-host option can be set
multiple times. Conflicts with the --no-hosts option.

--annotation=key=value
Add an annotation to the container. This option can be set multiple times.

--arch=ARCH
Override the architecture, defaults to hosts, of the image to be pulled. For example, arm.
Unless overridden, subsequent lookups of the same image in the local storage matches this
architecture, regardless of the host.

--attach, -a=stdin | stdout | stderr
Attach to STDIN, STDOUT or STDERR.

In foreground mode (the default when -d is not specified), podman run can start the
process in the container and attach the console to the process's standard input, output,
and error. It can even pretend to be a TTY (this is what most command-line executables
expect) and pass along signals. The -a option can be set for each of stdin, stdout, and
stderr.

--authfile=path
Path of the authentication file. Default is ${XDG_RUNTIME_DIR}/containers/auth.json on
Linux, and $HOME/.config/containers/auth.json on Windows/macOS. The file is created by
podman login. If the authorization state is not found there, $HOME/.docker/config.json is
checked, which is set using docker login.

Note: There is also the option to override the default path of the authentication file by
setting the REGISTRY_AUTH_FILE environment variable. This can be done with export
REGISTRY_AUTH_FILE=path.

--blkio-weight=weight
Block IO relative weight. The weight is a value between 10 and 1000.

This option is not supported on cgroups V1 rootless systems.

--blkio-weight-device=device:weight
Block IO relative device weight.

--cap-add=capability
Add Linux capabilities.

--cap-drop=capability
Drop Linux capabilities.

--cgroup-conf=KEY=VALUE
When running on cgroup v2, specify the cgroup file to write to and its value. For example
--cgroup-conf=memory.high=1073741824 sets the memory.high limit to 1GB.

--cgroup-parent=path
Path to cgroups under which the cgroup for the container is created. If the path is not
absolute, the path is considered to be relative to the cgroups path of the init process.
Cgroups are created if they do not already exist.

--cgroupns=mode
Set the cgroup namespace mode for the container.

• host: use the host's cgroup namespace inside the container.

• container:id: join the namespace of the specified container.

• private: create a new cgroup namespace.

• ns:path: join the namespace at the specified path.

If the host uses cgroups v1, the default is set to host. On cgroups v2, the default is
private.

--cgroups=how
Determines whether the container creates CGroups.

Default is enabled.

The enabled option creates a new cgroup under the cgroup-parent. The disabled option
forces the container to not create CGroups, and thus conflicts with CGroup options
(--cgroupns and --cgroup-parent). The no-conmon option disables a new CGroup only for the
conmon process. The split option splits the current CGroup in two sub-cgroups: one for
conmon and one for the container payload. It is not possible to set --cgroup-parent with
split.

--chrootdirs=path
Path to a directory inside the container that is treated as a chroot directory. Any
Podman managed file (e.g., /etc/resolv.conf, /etc/hosts, etc/hostname) that is mounted
into the root directory is mounted into that location as well. Multiple directories are
separated with a comma.

--cidfile=file
Write the container ID to file. The file is removed along with the container, except when
used with podman --remote run on detached containers.

--conmon-pidfile=file
Write the pid of the conmon process to a file. As conmon runs in a separate process than
Podman, this is necessary when using systemd to restart Podman containers. (This option
is not available with the remote Podman client, including Mac and Windows (excluding WSL2)
machines)

--cpu-period=limit
Set the CPU period for the Completely Fair Scheduler (CFS), which is a duration in
microseconds. Once the container's CPU quota is used up, it will not be scheduled to run
until the current period ends. Defaults to 100000 microseconds.

On some systems, changing the resource limits may not be allowed for non-root users. For
more details, see
https://github.com/containers/podman/blob/main/troubleshooting.md#26-running-containers-
with-resource-limits-fails-with-a-permissions-error

This option is not supported on cgroups V1 rootless systems.

--cpu-quota=limit
Limit the CPU Completely Fair Scheduler (CFS) quota.

Limit the container's CPU usage. By default, containers run with the full CPU resource.
The limit is a number in microseconds. If a number is provided, the container is allowed
to use that much CPU time until the CPU period ends (controllable via --cpu-period).

This option is not supported on cgroups V1 rootless systems.

--cpu-rt-period=microseconds
Limit the CPU real-time period in microseconds.

Limit the container's Real Time CPU usage. This option tells the kernel to restrict the
container's Real Time CPU usage to the period specified.

This option is only supported on cgroups V1 rootful systems.

--cpu-rt-runtime=microseconds
Limit the CPU real-time runtime in microseconds.

Limit the containers Real Time CPU usage. This option tells the kernel to limit the amount
of time in a given CPU period Real Time tasks may consume. Ex: Period of 1,000,000us and
Runtime of 950,000us means that this container can consume 95% of available CPU and leave
the remaining 5% to normal priority tasks.

The sum of all runtimes across containers cannot exceed the amount allotted to the parent
cgroup.

This option is only supported on cgroups V1 rootful systems.

--cpu-shares, -c=shares
CPU shares (relative weight).

By default, all containers get the same proportion of CPU cycles. This proportion can be
modified by changing the container's CPU share weighting relative to the combined weight
of all the running containers. Default weight is 1024.

The proportion only applies when CPU-intensive processes are running. When tasks in one
container are idle, other containers can use the left-over CPU time. The actual amount of
CPU time varies depending on the number of containers running on the system.

For example, consider three containers, one has a cpu-share of 1024 and two others have a
cpu-share setting of 512. When processes in all three containers attempt to use 100% of
CPU, the first container receives 50% of the total CPU time. If a fourth container is
added with a cpu-share of 1024, the first container only gets 33% of the CPU. The
remaining containers receive 16.5%, 16.5% and 33% of the CPU.

On a multi-core system, the shares of CPU time are distributed over all CPU cores. Even if
a container is limited to less than 100% of CPU time, it can use 100% of each individual
CPU core.

For example, consider a system with more than three cores. If the container C0 is started
with --cpu-shares=512 running one process, and another container C1 with --cpu-shares=1024
running two processes, this can result in the following division of CPU shares:

┌────┬───────────┬─────┬──────────────┐
│PID │ container │ CPU │ CPU share │
├────┼───────────┼─────┼──────────────┤
│100 │ C0 │ 0 │ 100% of CPU0 │
├────┼───────────┼─────┼──────────────┤
│101 │ C1 │ 1 │ 100% of CPU1 │
├────┼───────────┼─────┼──────────────┤
│102 │ C1 │ 2 │ 100% of CPU2 │
└────┴───────────┴─────┴──────────────┘

This option is not supported on cgroups V1 rootless systems.

--cpus=number
Number of CPUs. The default is 0.0 which means no limit. This is shorthand for --cpu-
period and --cpu-quota, therefore the option cannot be specified with --cpu-period or
--cpu-quota.

On some systems, changing the CPU limits may not be allowed for non-root users. For more
details, see https://github.com/containers/podman/blob/main/troubleshooting.md#26-running-
containers-with-resource-limits-fails-with-a-permissions-error

This option is not supported on cgroups V1 rootless systems.

--cpuset-cpus=number
CPUs in which to allow execution. Can be specified as a comma-separated list (e.g. 0,1),
as a range (e.g. 0-3), or any combination thereof (e.g. 0-3,7,11-15).

This option is not supported on cgroups V1 rootless systems.

--cpuset-mems=nodes
Memory nodes (MEMs) in which to allow execution (0-3, 0,1). Only effective on NUMA
systems.

If there are four memory nodes on the system (0-3), use --cpuset-mems=0,1 then processes
in the container only uses memory from the first two memory nodes.

This option is not supported on cgroups V1 rootless systems.

--decryption-key=key[:passphrase]
The [key[:passphrase]] to be used for decryption of images. Key can point to keys and/or
certificates. Decryption is tried with all keys. If the key is protected by a passphrase,
it is required to be passed in the argument and omitted otherwise.

--device=host-device[:container-device][:permissions]
Add a host device to the container. Optional permissions parameter can be used to specify
device permissions by combining r for read, w for write, and m for mknod(2).

Example: --device=/dev/sdc:/dev/xvdc:rwm.

Note: if host-device is a symbolic link then it is resolved first. The container only
stores the major and minor numbers of the host device.

Podman may load kernel modules required for using the specified device. The devices that
Podman loads modules for when necessary are: /dev/fuse.

In rootless mode, the new device is bind mounted in the container from the host rather
than Podman creating it within the container space. Because the bind mount retains its
SELinux label on SELinux systems, the container can get permission denied when accessing
the mounted device. Modify SELinux settings to allow containers to use all device labels
via the following command:

$ sudo setsebool -P container_use_devices=true

Note: if the user only has access rights via a group, accessing the device from inside a
rootless container fails. Use the --group-add keep-groups flag to pass the user's
supplementary group access into the container.

--device-cgroup-rule="type major:minor mode"
Add a rule to the cgroup allowed devices list. The rule is expected to be in the format
specified in the Linux kernel documentation admin-guide/cgroup-v1/devices: - type: a
(all), c (char), or b (block); - major and minor: either a number, or * for all; - mode: a
composition of r (read), w (write), and m (mknod(2)).

--device-read-bps=path:rate
Limit read rate (in bytes per second) from a device (e.g. --device-read-bps=/dev/sda:1mb).

This option is not supported on cgroups V1 rootless systems.

--device-read-iops=path:rate
Limit read rate (in IO operations per second) from a device (e.g. --device-read-
iops=/dev/sda:1000).

This option is not supported on cgroups V1 rootless systems.

--device-write-bps=path:rate
Limit write rate (in bytes per second) to a device (e.g. --device-write-bps=/dev/sda:1mb).

This option is not supported on cgroups V1 rootless systems.

--device-write-iops=path:rate
Limit write rate (in IO operations per second) to a device (e.g. --device-write-
iops=/dev/sda:1000).

This option is not supported on cgroups V1 rootless systems.

--disable-content-trust
This is a Docker-specific option to disable image verification to a container registry and
is not supported by Podman. This option is a NOOP and provided solely for scripting
compatibility.

--dns=ipaddr
Set custom DNS servers.

This option can be used to override the DNS configuration passed to the container.
Typically this is necessary when the host DNS configuration is invalid for the container
(e.g., 127.0.0.1). When this is the case the --dns flag is necessary for every run.

The special value none can be specified to disable creation of /etc/resolv.conf in the
container by Podman. The /etc/resolv.conf file in the image is used without changes.

This option cannot be combined with --network that is set to none or container:id.

--dns-option=option
Set custom DNS options. Invalid if using --dns-option with --network that is set to none
or container:id.

--dns-search=domain
Set custom DNS search domains. Invalid if using --dns-search with --network that is set to
none or container:id. Use --dns-search=. to remove the search domain.

--entrypoint="command" | '["command", arg1 , ...]'
Override the default ENTRYPOINT from the image.

The ENTRYPOINT of an image is similar to a COMMAND because it specifies what executable to
run when the container starts, but it is (purposely) more difficult to override. The
ENTRYPOINT gives a container its default nature or behavior. When the ENTRYPOINT is set,
the container runs as if it were that binary, complete with default options. More options
can be passed in via the COMMAND. But, if a user wants to run something else inside the
container, the --entrypoint option allows a new ENTRYPOINT to be specified.

Specify multi option commands in the form of a json string.

--env, -e=env
Set environment variables.

This option allows arbitrary environment variables that are available for the process to
be launched inside of the container. If an environment variable is specified without a
value, Podman checks the host environment for a value and set the variable only if it is
set on the host. As a special case, if an environment variable ending in * is specified
without a value, Podman searches the host environment for variables starting with the
prefix and adds those variables to the container.

See ⟨#environment⟩ note below for precedence and examples.

--env-file=file
Read in a line-delimited file of environment variables.

See ⟨#environment⟩ note below for precedence and examples.

--env-host
Use host environment inside of the container. See Environment note below for precedence.
(This option is not available with the remote Podman client, including Mac and Windows
(excluding WSL2) machines)

--env-merge=env
Preprocess default environment variables for the containers. For example if image contains
environment variable hello=world user can preprocess it using --env-merge
hello=${hello}-some so new value is hello=world-some.

Please note that if the environment variable hello is not present in the image, then it'll
be replaced by an empty string and so using --env-merge hello=${hello}-some would result
in the new value of hello=-some, notice the leading - delimiter.

--expose=port
Expose a port, or a range of ports (e.g. --expose=3300-3310) to set up port redirection on
the host system.

--gidmap=[flags]container_uid:from_uid[:amount]
Run the container in a new user namespace using the supplied GID mapping. This option
conflicts with the --userns and --subgidname options. This option provides a way to map
host GIDs to container GIDs in the same way as --uidmap maps host UIDs to container UIDs.
For details see --uidmap.

Note: the --gidmap option cannot be called in conjunction with the --pod option as a
gidmap cannot be set on the container level when in a pod.

--gpus=ENTRY
GPU devices to add to the container ('all' to pass all GPUs) Currently only Nvidia devices
are supported.

--group-add=group | keep-groups
Assign additional groups to the primary user running within the container process.

• keep-groups is a special flag that tells Podman to keep the supplementary group
access.

Allows container to use the user's supplementary group access. If file systems or devices
are only accessible by the rootless user's group, this flag tells the OCI runtime to pass
the group access into the container. Currently only available with the crun OCI runtime.
Note: keep-groups is exclusive, other groups cannot be specified with this flag. (Not
available for remote commands, including Mac and Windows (excluding WSL2) machines)

--group-entry=ENTRY
Customize the entry that is written to the /etc/group file within the container when
--user is used.

The variables $GROUPNAME, $GID, and $USERLIST are automatically replaced with their value
at runtime if present.

--health-cmd="command" | '["command", arg1 , ...]'
Set or alter a healthcheck command for a container. The command is a command to be
executed inside the container that determines the container health. The command is
required for other healthcheck options to be applied. A value of none disables existing
healthchecks.

Multiple options can be passed in the form of a JSON array; otherwise, the command is
interpreted as an argument to /bin/sh -c.

--health-interval=interval
Set an interval for the healthchecks. An interval of disable results in no automatic timer
setup. The default is 30s.

--health-on-failure=action
Action to take once the container transitions to an unhealthy state. The default is none.

• none: Take no action.

• kill: Kill the container.

• restart: Restart the container. Do not combine the restart action with the
--restart flag. When running inside of a systemd unit, consider using the kill
or stop action instead to make use of systemd's restart policy.

• stop: Stop the container.

--health-retries=retries
The number of retries allowed before a healthcheck is considered to be unhealthy. The
default value is 3.

--health-start-period=period
The initialization time needed for a container to bootstrap. The value can be expressed in
time format like 2m3s. The default value is 0s.

Note: The health check command is executed as soon as a container is started, if the
health check is successful the container's health state will be updated to healthy.
However, if the health check fails, the health state will stay as starting until either
the health check is successful or until the --health-start-period time is over. If the
health check command fails after the --health-start-period time is over, the health state
will be updated to unhealthy. The health check command is executed periodically based on
the value of --health-interval.

--health-startup-cmd="command" | '["command", arg1 , ...]'
Set a startup healthcheck command for a container. This command is executed inside the
container and is used to gate the regular healthcheck. When the startup command succeeds,
the regular healthcheck begins and the startup healthcheck ceases. Optionally, if the
command fails for a set number of attempts, the container is restarted. A startup
healthcheck can be used to ensure that containers with an extended startup period are not
marked as unhealthy until they are fully started. Startup healthchecks can only be used
when a regular healthcheck (from the container's image or the --health-cmd option) is also
set.

--health-startup-interval=interval
Set an interval for the startup healthcheck. An interval of disable results in no
automatic timer setup. The default is 30s.

--health-startup-retries=retries
The number of attempts allowed before the startup healthcheck restarts the container. If
set to 0, the container is never restarted. The default is 0.

--health-startup-success=retries
The number of successful runs required before the startup healthcheck succeeds and the
regular healthcheck begins. A value of 0 means that any success begins the regular
healthcheck. The default is 0.

--health-startup-timeout=timeout
The maximum time a startup healthcheck command has to complete before it is marked as
failed. The value can be expressed in a time format like 2m3s. The default value is 30s.

--health-timeout=timeout
The maximum time allowed to complete the healthcheck before an interval is considered
failed. Like start-period, the value can be expressed in a time format such as 1m22s. The
default value is 30s.

--help
Print usage statement

--hostname, -h=name
Container host name

Sets the container host name that is available inside the container. Can only be used with
a private UTS namespace --uts=private (default). If --pod is specified and the pod shares
the UTS namespace (default) the pod's hostname is used.

--hostuser=name
Add a user account to /etc/passwd from the host to the container. The Username or UID must
exist on the host system.

--http-proxy
By default proxy environment variables are passed into the container if set for the Podman
process. This can be disabled by setting the value to false. The environment variables
passed in include http_proxy, https_proxy, ftp_proxy, no_proxy, and also the upper case
versions of those. This option is only needed when the host system must use a proxy but
the container does not use any proxy. Proxy environment variables specified for the
container in any other way overrides the values that have been passed through from the
host. (Other ways to specify the proxy for the container include passing the values with
the --env flag, or hard coding the proxy environment at container build time.) When used
with the remote client it uses the proxy environment variables that are set on the server
process.

Defaults to true.

--image-volume=bind | tmpfs | ignore
Tells Podman how to handle the builtin image volumes. Default is bind.

• bind: An anonymous named volume is created and mounted into the container.

• tmpfs: The volume is mounted onto the container as a tmpfs, which allows the
users to create content that disappears when the container is stopped.

• ignore: All volumes are just ignored and no action is taken.

--init
Run an init inside the container that forwards signals and reaps processes. The
container-init binary is mounted at /run/podman-init. Mounting over /run breaks container
execution.

--init-ctr=type
(Pods only). When using pods, create an init style container, which is run after the
infra container is started but before regular pod containers are started. Init containers
are useful for running setup operations for the pod's applications.

Valid values for init-ctr type are always or once. The always value means the container
runs with each and every pod start, whereas the once value means the container only runs
once when the pod is started and then the container is removed.

Init containers are only run on pod start. Restarting a pod does not execute any init
containers. Furthermore, init containers can only be created in a pod when that pod is
not running.

--init-path=path
Path to the container-init binary.

--interactive, -i
When set to true, keep stdin open even if not attached. The default is false.

--ip=ipv4
Specify a static IPv4 address for the container, for example 10.88.64.128. This option
can only be used if the container is joined to only a single network - i.e.,
--network=network-name is used at most once - and if the container is not joining another
container's network namespace via --network=container:id. The address must be within the
network's IP address pool (default 10.88.0.0/16).

To specify multiple static IP addresses per container, set multiple networks using the
--network option with a static IP address specified for each using the ip mode for that
option.

--ip6=ipv6
Specify a static IPv6 address for the container, for example fd46:db93:aa76:ac37::10.
This option can only be used if the container is joined to only a single network - i.e.,
--network=network-name is used at most once - and if the container is not joining another
container's network namespace via --network=container:id. The address must be within the
network's IPv6 address pool.

To specify multiple static IPv6 addresses per container, set multiple networks using the
--network option with a static IPv6 address specified for each using the ip6 mode for that
option.

--ipc=ipc
Set the IPC namespace mode for a container. The default is to create a private IPC
namespace.

• "": Use Podman's default, defined in containers.conf.

• container:id: reuses another container's shared memory, semaphores, and message
queues

• host: use the host's shared memory, semaphores, and message queues inside the
container. Note: the host mode gives the container full access to local shared
memory and is therefore considered insecure.

• none: private IPC namespace, with /dev/shm not mounted.

• ns:path: path to an IPC namespace to join.

• private: private IPC namespace.

• shareable: private IPC namespace with a possibility to share it with other
containers.

--label, -l=key=value
Add metadata to a container.

--label-file=file
Read in a line-delimited file of labels.

--link-local-ip=ip
Not implemented.

--log-driver=driver
Logging driver for the container. Currently available options are k8s-file, journald,
none, passthrough and passthrough-tty, with json-file aliased to k8s-file for scripting
compatibility. (Default journald).

The podman info command below displays the default log-driver for the system.

$ podman info --format '{{ .Host.LogDriver }}'
journald

The passthrough driver passes down the standard streams (stdin, stdout, stderr) to the
container. It is not allowed with the remote Podman client, including Mac and Windows
(excluding WSL2) machines, and on a tty, since it is vulnerable to attacks via TIOCSTI.

The passthrough-tty driver is the same as passthrough except that it also allows it to be
used on a TTY if the user really wants it.

--log-opt=name=value
Logging driver specific options.

Set custom logging configuration. The following *name*s are supported:

path: specify a path to the log file
(e.g. --log-opt path=/var/log/container/mycontainer.json);

max-size: specify a max size of the log file
(e.g. --log-opt max-size=10mb);

tag: specify a custom log tag for the container
(e.g. --log-opt tag="{{.ImageName}}". It supports the same keys as podman inspect
--format. This option is currently supported only by the journald log driver.

--mac-address=address
Container network interface MAC address (e.g. 92:d0:c6:0a:29:33) This option can only be
used if the container is joined to only a single network - i.e., --network=network-name is
used at most once - and if the container is not joining another container's network
namespace via --network=container:id.

Remember that the MAC address in an Ethernet network must be unique. The IPv6 link-local
address is based on the device's MAC address according to RFC4862.

To specify multiple static MAC addresses per container, set multiple networks using the
--network option with a static MAC address specified for each using the mac mode for that
option.

--memory, -m=number[unit]
Memory limit. A unit can be b (bytes), k (kibibytes), m (mebibytes), or g (gibibytes).

Allows the memory available to a container to be constrained. If the host supports swap
memory, then the -m memory setting can be larger than physical RAM. If a limit of 0 is
specified (not using -m), the container's memory is not limited. The actual limit may be
rounded up to a multiple of the operating system's page size (the value is very large,
that's millions of trillions).

This option is not supported on cgroups V1 rootless systems.

--memory-reservation=number[unit]
Memory soft limit. A unit can be b (bytes), k (kibibytes), m (mebibytes), or g
(gibibytes).

After setting memory reservation, when the system detects memory contention or low memory,
containers are forced to restrict their consumption to their reservation. So always set
the value below --memory, otherwise the hard limit takes precedence. By default, memory
reservation is the same as memory limit.

This option is not supported on cgroups V1 rootless systems.

--memory-swap=number[unit]
A limit value equal to memory plus swap. A unit can be b (bytes), k (kibibytes), m
(mebibytes), or g (gibibytes).

Must be used with the -m (--memory) flag. The argument value must be larger than that of
-m (--memory) By default, it is set to double the value of --memory.

Set number to -1 to enable unlimited swap.

This option is not supported on cgroups V1 rootless systems.

--memory-swappiness=number
Tune a container's memory swappiness behavior. Accepts an integer between 0 and 100.

This flag is only supported on cgroups V1 rootful systems.

--mount=type=TYPE,TYPE-SPECIFIC-OPTION[,...]
Attach a filesystem mount to the container

Current supported mount TYPEs are bind, devpts, glob, image, ramfs, tmpfs and volume.

Options common to all mount types:

• src, source: mount source spec for bind, glob, and volume. Mandatory for bind
and glob.

• dst, destination, target: mount destination spec.

When source globs are specified without the destination directory, the files and
directories are mounted with their complete path within the container. When the
destination is specified, the files and directories matching the glob on the base file
name on the destination directory are mounted. The option
type=glob,src=/foo*,destination=/tmp/bar tells container engines to mount host files
matching /foo* to the /tmp/bar/ directory in the container.

Options specific to type=volume:

• ro, readonly: true or false (default if unspecified: false).

• U, chown: true or false (default if unspecified: false). Recursively change the
owner and group of the source volume based on the UID and GID of the container.

• idmap: If specified, create an idmapped mount to the target user namespace in the
container. The idmap option supports a custom mapping that can be different than
the user namespace used by the container. The mapping can be specified after the
idmap option like: idmap=uids=0-1-10#10-11-10;gids=0-100-10. For each triplet,
the first value is the start of the backing file system IDs that are mapped to
the second value on the host. The length of this mapping is given in the third
value. Multiple ranges are separated with #. If the specified mapping is
prepended with a '@' then the mapping is considered relative to the container
user namespace. The host ID for the mapping is changed to account for the
relative position of the container user in the container user namespace.

Options specific to type=image:

• rw, readwrite: true or false (default if unspecified: false).

Options specific to bind and glob:

• ro, readonly: true or false (default if unspecified: false).

• bind-propagation: shared, slave, private, unbindable, rshared, rslave,
runbindable, or rprivate (default).[1] ⟨#Footnote1⟩ See also mount(2).

• bind-nonrecursive: do not set up a recursive bind mount. By default it is
recursive.

• relabel: shared, private.

• idmap: true or false (default if unspecified: false). If true, create an
idmapped mount to the target user namespace in the container.

• U, chown: true or false (default if unspecified: false). Recursively change the
owner and group of the source volume based on the UID and GID of the container.

• no-dereference: do not dereference symlinks but copy the link source into the
mount destination.

Options specific to type=tmpfs and ramfs:

• ro, readonly: true or false (default if unspecified: false).

• tmpfs-size: Size of the tmpfs/ramfs mount, in bytes. Unlimited by default in
Linux.

• tmpfs-mode: Octal file mode of the tmpfs/ramfs (e.g. 700 or 0700.).

• tmpcopyup: Enable copyup from the image directory at the same location to the
tmpfs/ramfs. Used by default.

• notmpcopyup: Disable copying files from the image to the tmpfs/ramfs.

• U, chown: true or false (default if unspecified: false). Recursively change the
owner and group of the source volume based on the UID and GID of the container.

Options specific to type=devpts:

• uid: numeric UID of the file owner (default: 0).

• gid: numeric GID of the file owner (default: 0).

• mode: octal permission mask for the file (default: 600).

• max: maximum number of PTYs (default: 1048576).

Examples:

• type=bind,source=/path/on/host,destination=/path/in/container

• type=bind,src=/path/on/host,dst=/path/in/container,relabel=shared

• type=bind,src=/path/on/host,dst=/path/in/container,relabel=shared,U=true

• type=devpts,destination=/dev/pts

• type=glob,src=/usr/lib/libfoo*,destination=/usr/lib,ro=true

• type=image,source=fedora,destination=/fedora-image,rw=true

• type=ramfs,tmpfs-size=512M,destination=/path/in/container

• type=tmpfs,tmpfs-size=512M,destination=/path/in/container

• type=tmpfs,destination=/path/in/container,noswap

• type=volume,source=vol1,destination=/path/in/container,ro=true

--name=name
Assign a name to the container.

The operator can identify a container in three ways:

• UUID long identifier
(“f78375b1c487e03c9438c729345e54db9d20cfa2ac1fc3494b6eb60872e74778”);

• UUID short identifier (“f78375b1c487”);

• Name (“jonah”).

Podman generates a UUID for each container, and if a name is not assigned to the container
with --name then it generates a random string name. The name can be useful as a more
human-friendly way to identify containers. This works for both background and foreground
containers.

--network=mode, --net
Set the network mode for the container.

Valid mode values are:

• bridge[:OPTIONS,...]: Create a network stack on the default bridge. This is the
default for rootful containers. It is possible to specify these additional
options:

• alias=name: Add network-scoped alias for the container.

• ip=IPv4: Specify a static ipv4 address for this container.

• ip=IPv6: Specify a static ipv6 address for this container.

• mac=MAC: Specify a static mac address for this container.

• interface_name: Specify a name for the created network interface inside the
container.

For example, to set a static ipv4 address and a static mac address, use --network
bridge:ip=10.88.0.10,mac=44:33:22:11:00:99.

• <network name or ID>[:OPTIONS,...]: Connect to a user-defined network; this is
the network name or ID from a network created by podman network create. Using the
network name implies the bridge network mode. It is possible to specify the same
options described under the bridge mode above. Use the --network option multiple
times to specify additional networks.

For backwards compatibility it is also possible to specify comma-separated networks on the
first --network argument, however this prevents you from using the options described under
the bridge section above. - none: Create a network namespace for the container but do not
configure network interfaces for it, thus the container has no network connectivity. -
container:id: Reuse another container's network stack. - host: Do not create a network
namespace, the container uses the host's network. Note: The host mode gives the container
full access to local system services such as D-bus and is therefore considered insecure.
- ns:path: Path to a network namespace to join. - private: Create a new namespace for the
container. This uses the bridge mode for rootful containers and slirp4netns for rootless
ones. - slirp4netns[:OPTIONS,...]: use slirp4netns(1) to create a user network stack.
This is the default for rootless containers. It is possible to specify these additional
options, they can also be set with network_cmd_options in containers.conf:
- allow_host_loopback=true|false: Allow slirp4netns to reach the host loopback IP
(default is 10.0.2.2 or the second IP from slirp4netns cidr subnet when changed, see the
cidr option below). The default is false.
- mtu=MTU: Specify the MTU to use for this network. (Default is 65520).
- cidr=CIDR: Specify ip range to use for this network. (Default is 10.0.2.0/24).
- enable_ipv6=true|false: Enable IPv6. Default is true. (Required for outbound_addr6).
- outbound_addr=INTERFACE: Specify the outbound interface slirp binds to (ipv4 traffic
only).
- outbound_addr=IPv4: Specify the outbound ipv4 address slirp binds to.
- outbound_addr6=INTERFACE: Specify the outbound interface slirp binds to (ipv6 traffic
only).
- outbound_addr6=IPv6: Specify the outbound ipv6 address slirp binds to.
- port_handler=rootlesskit: Use rootlesskit for port forwarding. Default.
Note: Rootlesskit changes the source IP address of incoming packets to an IP address in
the container network namespace, usually 10.0.2.100. If the application requires the real
source IP address, e.g. web server logs, use the slirp4netns port handler. The rootlesskit
port handler is also used for rootless containers when connected to user-defined networks.
- port_handler=slirp4netns: Use the slirp4netns port forwarding, it is slower than
rootlesskit but preserves the correct source IP address. This port handler cannot be used
for user-defined networks.

• pasta[:OPTIONS,...]: use pasta(1) to create a user-mode networking stack.
This is only supported in rootless mode.
By default, IPv4 and IPv6 addresses and routes, as well as the pod interface
name, are copied from the host. If port forwarding isn't configured, ports are
forwarded dynamically as services are bound on either side (init namespace or
container namespace). Port forwarding preserves the original source IP address.
Options described in pasta(1) can be specified as comma-separated arguments.
In terms of pasta(1) options, --config-net is given by default, in order to
configure networking when the container is started, and --no-map-gw is also
assumed by default, to avoid direct access from container to host using the
gateway address. The latter can be overridden by passing --map-gw in the pasta-
specific options (despite not being an actual pasta(1) option).
Also, -t none and -u none are passed if, respectively, no TCP or UDP port
forwarding from host to container is configured, to disable automatic port
forwarding based on bound ports. Similarly, -T none and -U none are given to
disable the same functionality from container to host.
Some examples:

• pasta:--map-gw: Allow the container to directly reach the host using the
gateway address.

• pasta:--mtu,1500: Specify a 1500 bytes MTU for the tap interface in the
container.

• pasta:--ipv4-only,-a,10.0.2.0,-n,24,-g,10.0.2.2,--dns-
forward,10.0.2.3,-m,1500,--no-ndp,--no-dhcpv6,--no-dhcp, equivalent to default
slirp4netns(1) options: disable IPv6, assign 10.0.2.0/24 to the tap0 interface
in the container, with gateway 10.0.2.3, enable DNS forwarder reachable at
10.0.2.3, set MTU to 1500 bytes, disable NDP, DHCPv6 and DHCP support.

• pasta:-I,tap0,--ipv4-only,-a,10.0.2.0,-n,24,-g,10.0.2.2,--dns-
forward,10.0.2.3,--no-ndp,--no-dhcpv6,--no-dhcp, equivalent to default
slirp4netns(1) options with Podman overrides: same as above, but leave the MTU
to 65520 bytes

• pasta:-t,auto,-u,auto,-T,auto,-U,auto: enable automatic port forwarding based
on observed bound ports from both host and container sides

• pasta:-T,5201: enable forwarding of TCP port 5201 from container to host, using
the loopback interface instead of the tap interface for improved performance

Invalid if using --dns, --dns-option, or --dns-search with --network set to none or
container:id.

If used together with --pod, the container does not join the pod's network namespace.

--network-alias=alias
Add a network-scoped alias for the container, setting the alias for all networks that the
container joins. To set a name only for a specific network, use the alias option as
described under the --network option. If the network has DNS enabled (podman network
inspect -f {{.DNSEnabled}} <name>), these aliases can be used for name resolution on the
given network. This option can be specified multiple times. NOTE: When using CNI a
container only has access to aliases on the first network that it joins. This limitation
does not exist with netavark/aardvark-dns.

--no-healthcheck
Disable any defined healthchecks for container.

--no-hosts
Do not create /etc/hosts for the container. By default, Podman manages /etc/hosts, adding
the container's own IP address and any hosts from --add-host. --no-hosts disables this,
and the image's /etc/hosts is preserved unmodified.

This option conflicts with --add-host.

--oom-kill-disable
Whether to disable OOM Killer for the container or not.

This flag is not supported on cgroups V2 systems.

--oom-score-adj=num
Tune the host's OOM preferences for containers (accepts values from -1000 to 1000).

When running in rootless mode, the specified value can't be lower than the oom_score_adj
for the current process. In this case, the oom-score-adj is clamped to the current process
value.

--os=OS
Override the OS, defaults to hosts, of the image to be pulled. For example, windows.
Unless overridden, subsequent lookups of the same image in the local storage matches this
OS, regardless of the host.

--passwd-entry=ENTRY
Customize the entry that is written to the /etc/passwd file within the container when
--passwd is used.

The variables $USERNAME, $UID, $GID, $NAME, $HOME are automatically replaced with their
value at runtime.

--personality=persona
Personality sets the execution domain via Linux personality(2).

--pid=mode
Set the PID namespace mode for the container. The default is to create a private PID
namespace for the container.

• container:id: join another container's PID namespace;

• host: use the host's PID namespace for the container. Note the host mode gives
the container full access to local PID and is therefore considered insecure;

• ns:path: join the specified PID namespace;

• private: create a new namespace for the container (default).

--pidfile=path
When the pidfile location is specified, the container process' PID is written to the
pidfile. (This option is not available with the remote Podman client, including Mac and
Windows (excluding WSL2) machines) If the pidfile option is not specified, the container
process' PID is written to /run/containers/storage/${storage-
driver}-containers/$CID/userdata/pidfile.

After the container is started, the location for the pidfile can be discovered with the
following podman inspect command:

$ podman inspect --format '{{ .PidFile }}' $CID
/run/containers/storage/${storage-driver}-containers/$CID/userdata/pidfile

--pids-limit=limit
Tune the container's pids limit. Set to -1 to have unlimited pids for the container. The
default is 2048 on systems that support "pids" cgroup controller.

--platform=OS/ARCH
Specify the platform for selecting the image. (Conflicts with --arch and --os) The
--platform option can be used to override the current architecture and operating system.
Unless overridden, subsequent lookups of the same image in the local storage matches this
platform, regardless of the host.

--pod=name
Run container in an existing pod. Podman makes the pod automatically if the pod name is
prefixed with new:. To make a pod with more granular options, use the podman pod create
command before creating a container. When a container is run with a pod with an infra-
container, the infra-container is started first.

--pod-id-file=file
Run container in an existing pod and read the pod's ID from the specified file. When a
container is run within a pod which has an infra-container, the infra-container starts
first.

--privileged
Give extended privileges to this container. The default is false.

By default, Podman containers are unprivileged (=false) and cannot, for example, modify
parts of the operating system. This is because by default a container is only allowed
limited access to devices. A "privileged" container is given the same access to devices as
the user launching the container, with the exception of virtual consoles (/dev/tty\d+)
when running in systemd mode (--systemd=always).

A privileged container turns off the security features that isolate the container from the
host. Dropped Capabilities, limited devices, read-only mount points, Apparmor/SELinux
separation, and Seccomp filters are all disabled. Due to the disabled security features,
the privileged field should almost never be set as containers can easily break out of
confinement.

Containers running in a user namespace (e.g., rootless containers) cannot have more
privileges than the user that launched them.

--publish, -p=[[ip:][hostPort]:]containerPort[/protocol]
Publish a container's port, or range of ports, to the host.

Both hostPort and containerPort can be specified as a range of ports. When specifying
ranges for both, the number of container ports in the range must match the number of host
ports in the range.

If host IP is set to 0.0.0.0 or not set at all, the port is bound on all IPs on the host.

By default, Podman publishes TCP ports. To publish a UDP port instead, give udp as
protocol. To publish both TCP and UDP ports, set --publish twice, with tcp, and udp as
protocols respectively. Rootful containers can also publish ports using the sctp protocol.

Host port does not have to be specified (e.g. podman run -p 127.0.0.1::80). If it is not,
the container port is randomly assigned a port on the host.

Use podman port to see the actual mapping: podman port $CONTAINER $CONTAINERPORT.

Note that the network drivers macvlan and ipvlan do not support port forwarding, it will
have no effect on these networks.

Note: If a container runs within a pod, it is not necessary to publish the port for the
containers in the pod. The port must only be published by the pod itself. Pod network
stacks act like the network stack on the host - when there are a variety of containers in
the pod, and programs in the container, all sharing a single interface and IP address, and
associated ports. If one container binds to a port, no other container can use that port
within the pod while it is in use. Containers in the pod can also communicate over
localhost by having one container bind to localhost in the pod, and another connect to
that port.

--publish-all, -P
Publish all exposed ports to random ports on the host interfaces. The default is false.

When set to true, publish all exposed ports to the host interfaces. If the operator uses
-P (or -p) then Podman makes the exposed port accessible on the host and the ports are
available to any client that can reach the host.

When using this option, Podman binds any exposed port to a random port on the host within
an ephemeral port range defined by /proc/sys/net/ipv4/ip_local_port_range. To find the
mapping between the host ports and the exposed ports, use podman port.

--pull=policy
Pull image policy. The default is missing.

• always: Always pull the image and throw an error if the pull fails.

• missing: Pull the image only when the image is not in the local containers
storage. Throw an error if no image is found and the pull fails.

• never: Never pull the image but use the one from the local containers storage.
Throw an error if no image is found.

• newer: Pull if the image on the registry is newer than the one in the local
containers storage. An image is considered to be newer when the digests are
different. Comparing the time stamps is prone to errors. Pull errors are
suppressed if a local image was found.

--quiet, -q
Suppress output information when pulling images

--rdt-class=intel-rdt-class-of-service
Rdt-class sets the class of service (CLOS or COS) for the container to run in. Based on
the Cache Allocation Technology (CAT) feature that is part of Intel's Resource Director
Technology (RDT) feature set, all container processes will run within the pre-configured
COS, representing a part of the cache. The COS has to be created and configured using a
pseudo file system (usually mounted at /sys/fs/resctrl) that the resctrl kernel driver
provides. Assigning the container to a COS requires root privileges and thus doesn't work
in a rootless environment. Currently, the feature is only supported using runc as a
runtime. See ⟨https://docs.kernel.org/arch/x86/resctrl.html⟩ for more details on creating
a COS before a container can be assigned to it.

--read-only
Mount the container's root filesystem as read-only.

By default, container root filesystems are writable, allowing processes to write files
anywhere. By specifying the --read-only flag, the containers root filesystem are mounted
read-only prohibiting any writes.

--read-only-tmpfs
When running --read-only containers, mount a read-write tmpfs on /dev, /dev/shm, /run,
/tmp, and /var/tmp. The default is true.

┌────────────┬───────────────────┬─────┬──────────────────────┐
│--read-only │ --read-only-tmpfs │ / │ /run, /tmp, /var/tmp │
├────────────┼───────────────────┼─────┼──────────────────────┤
│true │ true │ r/o │ r/w │
├────────────┼───────────────────┼─────┼──────────────────────┤
│true │ false │ r/o │ r/o │
├────────────┼───────────────────┼─────┼──────────────────────┤
│false │ false │ r/w │ r/w │
├────────────┼───────────────────┼─────┼──────────────────────┤
│false │ true │ r/w │ r/w │
└────────────┴───────────────────┴─────┴──────────────────────┘

When --read-only=true and --read-only-tmpfs=true additional tmpfs are mounted on the /tmp,
/run, and /var/tmp directories.

When --read-only=true and --read-only-tmpfs=false /dev and /dev/shm are marked Read/Only
and no tmpfs are mounted on /tmp, /run and /var/tmp. The directories are exposed from the
underlying image, meaning they are read-only by default. This makes the container totally
read-only. No writable directories exist within the container. In this mode writable
directories need to be added via external volumes or mounts.

By default, when --read-only=false, the /dev and /dev/shm are read/write, and the /tmp,
/run, and /var/tmp are read/write directories from the container image.

--replace
If another container with the same name already exists, replace and remove it. The default
is false.

--requires=container
Specify one or more requirements. A requirement is a dependency container that is started
before this container. Containers can be specified by name or ID, with multiple
containers being separated by commas.

--restart=policy
Restart policy to follow when containers exit. Restart policy does not take effect if a
container is stopped via the podman kill or podman stop commands.

Valid policy values are:

• no : Do not restart containers on exit

• never : Synonym for no; do not restart containers on exit

• on-failure[:max_retries] : Restart containers when they exit with a non-zero exit
code, retrying indefinitely or until the optional max_retries count is hit

• always : Restart containers when they exit, regardless of
status, retrying indefinitely

• unless-stopped : Identical to always

Podman provides a systemd unit file, podman-restart.service, which restarts containers
after a system reboot.

When running containers in systemd services, use the restart functionality provided by
systemd. In other words, do not use this option in a container unit, instead set the
Restart= systemd directive in the [Service] section. See podman-systemd.unit(5) and
systemd.service(5).

--retry=attempts
Number of times to retry pulling or pushing images between the registry and local storage
in case of failure. Default is 3.

--retry-delay=duration
Duration of delay between retry attempts when pulling or pushing images between the
registry and local storage in case of failure. The default is to start at two seconds and
then exponentially back off. The delay is used when this value is set, and no exponential
back off occurs.

--rm
Automatically remove the container and any anonymous unnamed volume associated with the
container when it exits. The default is false.

--rootfs
If specified, the first argument refers to an exploded container on the file system.

This is useful to run a container without requiring any image management, the rootfs of
the container is assumed to be managed externally.

Overlay Rootfs Mounts

The :O flag tells Podman to mount the directory from the rootfs path as storage using the
overlay file system. The container processes can modify content within the mount point
which is stored in the container storage in a separate directory. In overlay terms, the
source directory is the lower, and the container storage directory is the upper.
Modifications to the mount point are destroyed when the container finishes executing,
similar to a tmpfs mount point being unmounted.

Note: On SELinux systems, the rootfs needs the correct label, which is by default
unconfined_u:object_r:container_file_t:s0.

idmap

If idmap is specified, create an idmapped mount to the target user namespace in the
container. The idmap option supports a custom mapping that can be different than the user
namespace used by the container. The mapping can be specified after the idmap option
like: idmap=uids=0-1-10#10-11-10;gids=0-100-10. For each triplet, the first value is the
start of the backing file system IDs that are mapped to the second value on the host. The
length of this mapping is given in the third value. Multiple ranges are separated with #.

--sdnotify=container | conmon | healthy | ignore
Determines how to use the NOTIFY_SOCKET, as passed with systemd and Type=notify.

Default is container, which means allow the OCI runtime to proxy the socket into the
container to receive ready notification. Podman sets the MAINPID to conmon's pid. The
conmon option sets MAINPID to conmon's pid, and sends READY when the container has
started. The socket is never passed to the runtime or the container. The healthy option
sets MAINPID to conmon's pid, and sends READY when the container has turned healthy;
requires a healthcheck to be set. The socket is never passed to the runtime or the
container. The ignore option removes NOTIFY_SOCKET from the environment for itself and
child processes, for the case where some other process above Podman uses NOTIFY_SOCKET and
Podman does not use it.

--seccomp-policy=policy
Specify the policy to select the seccomp profile. If set to image, Podman looks for a
"io.containers.seccomp.profile" label in the container-image config and use its value as a
seccomp profile. Otherwise, Podman follows the default policy by applying the default
profile unless specified otherwise via --security-opt seccomp as described below.

Note that this feature is experimental and may change in the future.

--secret=secret[,opt=opt ...]
Give the container access to a secret. Can be specified multiple times.

A secret is a blob of sensitive data which a container needs at runtime but is not stored
in the image or in source control, such as usernames and passwords, TLS certificates and
keys, SSH keys or other important generic strings or binary content (up to 500 kb in
size).

When secrets are specified as type mount, the secrets are copied and mounted into the
container when a container is created. When secrets are specified as type env, the secret
is set as an environment variable within the container. Secrets are written in the
container at the time of container creation, and modifying the secret using podman secret
commands after the container is created affects the secret inside the container.

Secrets and its storage are managed using the podman secret command.

Secret Options

• type=mount|env : How the secret is exposed to the container.
mount mounts the secret into the container as a file.
env exposes the secret as an environment variable.
Defaults to mount.

• target=target : Target of secret.
For mounted secrets, this is the path to the secret inside
the container.
If a fully qualified path is provided, the secret is mounted
at that location.
Otherwise, the secret is mounted to
/run/secrets/target for linux containers or
/var/run/secrets/target for freebsd containers.
If the target is not set, the secret is mounted to
/run/secrets/secretname by default.
For env secrets, this is the environment variable key.
Defaults to secretname.

• uid=0 : UID of secret. Defaults to 0. Mount secret type only.

• gid=0 : GID of secret. Defaults to 0. Mount secret type only.

• mode=0 : Mode of secret. Defaults to 0444. Mount secret type only.

Examples

Mount at /my/location/mysecret with UID 1:

--secret mysecret,target=/my/location/mysecret,uid=1

Mount at /run/secrets/customtarget with mode 0777:

--secret mysecret,target=customtarget,mode=0777

Create a secret environment variable called ENVSEC:

--secret mysecret,type=env,target=ENVSEC

--security-opt=option
Security Options

• apparmor=unconfined : Turn off apparmor confinement for the container

• apparmor=alternate-profile : Set the apparmor confinement profile for the
container

• label=user:USER: Set the label user for the container processes

• label=role:ROLE: Set the label role for the container processes

• label=type:TYPE: Set the label process type for the container processes

• label=level:LEVEL: Set the label level for the container processes

• label=filetype:TYPE: Set the label file type for the container files

• label=disable: Turn off label separation for the container

Note: Labeling can be disabled for all containers by setting label=false in the
containers.conf (/etc/containers/containers.conf or
$HOME/.config/containers/containers.conf) file.

• label=nested: Allows SELinux modifications within the container. Containers are
allowed to modify SELinux labels on files and processes, as long as SELinux
policy allows. Without nested, containers view SELinux as disabled, even when it
is enabled on the host. Containers are prevented from setting any labels.

• mask=/path/1:/path/2: The paths to mask separated by a colon. A masked path
cannot be accessed inside the container.

• no-new-privileges: Disable container processes from gaining additional
privileges.

• seccomp=unconfined: Turn off seccomp confinement for the container.

• seccomp=profile.json: JSON file to be used as a seccomp filter. Note that the
io.podman.annotations.seccomp annotation is set with the specified value as shown
in podman inspect.

• proc-opts=OPTIONS : Comma-separated list of options to use for the /proc mount.
More details for the possible mount options are specified in the proc(5) man
page.

• unmask=ALL or /path/1:/path/2, or shell expanded paths (/proc/*): Paths to unmask
separated by a colon. If set to ALL, it unmasks all the paths that are masked or
made read-only by default. The default masked paths are /proc/acpi, /proc/kcore,
/proc/keys, /proc/latency_stats, /proc/sched_debug, /proc/scsi, /proc/timer_list,
/proc/timer_stats, /sys/firmware, and /sys/fs/selinux,
/sys/devices/virtual/powercap. The default paths that are read-only are
/proc/asound, /proc/bus, /proc/fs, /proc/irq, /proc/sys, /proc/sysrq-trigger,
/sys/fs/cgroup.

Note: Labeling can be disabled for all containers by setting label=false in the
containers.conf(5) file.

--shm-size=number[unit]
Size of /dev/shm. A unit can be b (bytes), k (kibibytes), m (mebibytes), or g (gibibytes).
If the unit is omitted, the system uses bytes. If the size is omitted, the default is 64m.
When size is 0, there is no limit on the amount of memory used for IPC by the container.
This option conflicts with --ipc=host.

--shm-size-systemd=number[unit]
Size of systemd-specific tmpfs mounts such as /run, /run/lock, /var/log/journal and /tmp.
A unit can be b (bytes), k (kibibytes), m (mebibytes), or g (gibibytes). If the unit is
omitted, the system uses bytes. If the size is omitted, the default is 64m. When size is
0, the usage is limited to 50% of the host's available memory.

--stop-signal=signal
Signal to stop a container. Default is SIGTERM.

--stop-timeout=seconds
Timeout to stop a container. Default is 10. Remote connections use local containers.conf
for defaults.

--subgidname=name
Run the container in a new user namespace using the map with name in the /etc/subgid file.
If running rootless, the user needs to have the right to use the mapping. See subgid(5).
This flag conflicts with --userns and --gidmap.

--subuidname=name
Run the container in a new user namespace using the map with name in the /etc/subuid file.
If running rootless, the user needs to have the right to use the mapping. See subuid(5).
This flag conflicts with --userns and --uidmap.

--sysctl=name=value
Configure namespaced kernel parameters at runtime.

For the IPC namespace, the following sysctls are allowed:

• kernel.msgmax

• kernel.msgmnb

• kernel.msgmni

• kernel.sem

• kernel.shmall

• kernel.shmmax

• kernel.shmmni

• kernel.shm_rmid_forced

• Sysctls beginning with fs.mqueue.*

Note: if using the --ipc=host option, the above sysctls are not allowed.

For the network namespace, only sysctls beginning with net.* are allowed.

Note: if using the --network=host option, the above sysctls are not allowed.

--systemd=true | false | always
Run container in systemd mode. The default is true.

• true enables systemd mode only when the command executed inside the container is
systemd, /usr/sbin/init, /sbin/init or /usr/local/sbin/init.

• false disables systemd mode.

• always enforces the systemd mode to be enabled.

Running the container in systemd mode causes the following changes:

• Podman mounts tmpfs file systems on the following directories

• /run

• /run/lock

• /tmp

• /sys/fs/cgroup/systemd (on a cgroup v1 system)

• /var/lib/journal

• Podman sets the default stop signal to SIGRTMIN+3.

• Podman sets container_uuid environment variable in the container to the first 32
characters of the container ID.

• Podman does not mount virtual consoles (/dev/tty\d+) when running with
--privileged.

• On cgroup v2, /sys/fs/cgroup is mounted writeable.

This allows systemd to run in a confined container without any modifications.

Note that on SELinux systems, systemd attempts to write to the cgroup file system.
Containers writing to the cgroup file system are denied by default. The
container_manage_cgroup boolean must be enabled for this to be allowed on an SELinux
separated system.

setsebool -P container_manage_cgroup true

--timeout=seconds
Maximum time a container is allowed to run before conmon sends it the kill signal. By
default containers run until they exit or are stopped by podman stop.

--tls-verify
Require HTTPS and verify certificates when contacting registries (default: true). If
explicitly set to true, TLS verification is used. If set to false, TLS verification is
not used. If not specified, TLS verification is used unless the target registry is listed
as an insecure registry in containers-registries.conf(5)

--tmpfs=fs
Create a tmpfs mount.

Mount a temporary filesystem (tmpfs) mount into a container, for example:

$ podman create -d --tmpfs /tmp:rw,size=787448k,mode=1777 my_image

This command mounts a tmpfs at /tmp within the container. The supported mount options are
the same as the Linux default mount flags. If no options are specified, the system uses
the following options: rw,noexec,nosuid,nodev.

--tty, -t
Allocate a pseudo-TTY. The default is false.

When set to true, Podman allocates a pseudo-tty and attach to the standard input of the
container. This can be used, for example, to run a throwaway interactive shell.

NOTE: The --tty flag prevents redirection of standard output. It combines STDOUT and
STDERR, it can insert control characters, and it can hang pipes. This option is only used
when run interactively in a terminal. When feeding input to Podman, use -i only, not -it.

--tz=timezone
Set timezone in container. This flag takes area-based timezones, GMT time, as well as
local, which sets the timezone in the container to match the host machine. See
/usr/share/zoneinfo/ for valid timezones. Remote connections use local containers.conf
for defaults

--uidmap=[flags]container_uid:from_uid[:amount]
Run the container in a new user namespace using the supplied UID mapping. This option
conflicts with the --userns and --subuidname options. This option provides a way to map
host UIDs to container UIDs. It can be passed several times to map different ranges.

The possible values of the optional flags are discussed further down on this page. The
amount value is optional and assumed to be 1 if not given.

The from_uid value is based upon the user running the command, either rootful or rootless
users.

• rootful user: [flags]container_uid:host_uid[:amount]

• rootless user: [flags]container_uid:intermediate_uid[:amount]

Rootful mappings

When podman create is called by a privileged user, the option --uidmap works as a direct
mapping between host UIDs and container UIDs.

host UID -> container UID

The amount specifies the number of consecutive UIDs that is mapped. If for example amount
is 4 the mapping looks like:

┌─────────────┬───────────────────┐
│host UID │ container UID │
├─────────────┼───────────────────┤
│from_uid │ container_uid │
├─────────────┼───────────────────┤
│from_uid + 1 │ container_uid + 1 │
├─────────────┼───────────────────┤
│from_uid + 2 │ container_uid + 2 │
├─────────────┼───────────────────┤
│from_uid + 3 │ container_uid + 3 │
└─────────────┴───────────────────┘

Rootless mappings

When podman create is called by an unprivileged user (i.e. running rootless), the value
from_uid is interpreted as an "intermediate UID". In the rootless case, host UIDs are not
mapped directly to container UIDs. Instead the mapping happens over two mapping steps:

host UID -> intermediate UID -> container UID

The --uidmap option only influences the second mapping step.

The first mapping step is derived by Podman from the contents of the file /etc/subuid and
the UID of the user calling Podman.

First mapping step:

┌────────────────────┬──────────────────┐
│host UID │ intermediate UID │
├────────────────────┼──────────────────┤
│UID for Podman user │ 0 │
├────────────────────┼──────────────────┤
│1st subordinate UID │ 1 │
├────────────────────┼──────────────────┤
│2nd subordinate UID │ 2 │
├────────────────────┼──────────────────┤
│3rd subordinate UID │ 3 │
├────────────────────┼──────────────────┤
│nth subordinate UID │ n │
└────────────────────┴──────────────────┘

To be able to use intermediate UIDs greater than zero, the user needs to have subordinate
UIDs configured in /etc/subuid. See subuid(5).

The second mapping step is configured with --uidmap.

If for example amount is 5 the second mapping step looks like:

┌─────────────────┬───────────────────┐
│intermediate UID │ container UID │
├─────────────────┼───────────────────┤
│from_uid │ container_uid │
├─────────────────┼───────────────────┤
│from_uid + 1 │ container_uid + 1 │
├─────────────────┼───────────────────┤
│from_uid + 2 │ container_uid + 2 │
├─────────────────┼───────────────────┤
│from_uid + 3 │ container_uid + 3 │
├─────────────────┼───────────────────┤
│from_uid + 4 │ container_uid + 4 │
└─────────────────┴───────────────────┘

When running as rootless, Podman uses all the ranges configured in the /etc/subuid file.

The current user ID is mapped to UID=0 in the rootless user namespace. Every additional
range is added sequentially afterward:

┌──────────────────────┬─────────────────────────┬──────────────────────┐
│host │ rootless user namespace │ length │
├──────────────────────┼─────────────────────────┼──────────────────────┤
│$UID │ 0 │ 1 │
├──────────────────────┼─────────────────────────┼──────────────────────┤
│1 │ $FIRST_RANGE_ID │ $FIRST_RANGE_LENGTH │
├──────────────────────┼─────────────────────────┼──────────────────────┤
│1+$FIRST_RANGE_LENGTH │ $SECOND_RANGE_ID │ $SECOND_RANGE_LENGTH │
└──────────────────────┴─────────────────────────┴──────────────────────┘

Referencing a host ID from the parent namespace

As a rootless user, the given host ID in --uidmap or --gidmap is mapped from the
intermediate namespace generated by Podman. Sometimes it is desirable to refer directly at
the host namespace. It is possible to manually do so, by running podman unshare cat
/proc/self/gid_map, finding the desired host id at the second column of the output, and
getting the corresponding intermediate id from the first column.

Podman can perform all that by preceding the host id in the mapping with the @ symbol. For
instance, by specifying --gidmap 100000:@2000:1, podman will look up the intermediate id
corresponding to host id 2000 and it will map the found intermediate id to the container
id 100000. The given host id must have been subordinated (otherwise it would not be mapped
into the intermediate space in the first place).

If the length is greater than one, for instance with --gidmap 100000:@2000:2, Podman will
map host ids 2000 and 2001 to 100000 and 100001, respectively, regardless of how the
intermediate mapping is defined.

Extending previous mappings

Some mapping modifications may be cumbersome. For instance, a user starts with a mapping
such as --gidmap="0:0:65000", that needs to be changed such as the parent id 1000 is
mapped to container id 100000 instead, leaving container id 1 unassigned. The
corresponding --gidmap becomes --gidmap="0:0:1" --gidmap="2:2:65534"
--gidmap="100000:1:1".

This notation can be simplified using the + flag, that takes care of breaking previous
mappings removing any conflicting assignment with the given mapping. The flag is given
before the container id as follows: --gidmap="0:0:65000" --gidmap="+100000:1:1"

┌─────┬─────────────┬─────────────────────────────┐
│Flag │ Example │ Description │
├─────┼─────────────┼─────────────────────────────┤
│+ │ +100000:1:1 │ Extend the previous mapping │
└─────┴─────────────┴─────────────────────────────┘

This notation leads to gaps in the assignment, so it may be convenient to fill those gaps
afterwards: --gidmap="0:0:65000" --gidmap="+100000:1:1" --gidmap="1:65001:1"

One specific use case for this flag is in the context of rootless users. A rootless user
may specify mappings with the + flag as in --gidmap="+100000:1:1". Podman will then "fill
the gaps" starting from zero with all the remaining intermediate ids. This is convenient
when a user wants to map a specific intermediate id to a container id, leaving the rest of
subordinate ids to be mapped by Podman at will.

Passing only one of --uidmap or --gidmap

Usually, subordinated user and group ids are assigned simultaneously, and for any user the
subordinated user ids match the subordinated group ids. For convenience, if only one of
--uidmap or --gidmap is given, podman assumes the mapping refers to both UIDs and GIDs and
applies the given mapping to both. If only one value of the two needs to be changed, the
mappings should include the u or the g flags to specify that they only apply to UIDs or
GIDs and should not be copied over.

┌─────┬───────────────┬──────────────────────────┐
│flag │ Example │ Description │
├─────┼───────────────┼──────────────────────────┤
│u │ u20000:2000:1 │ The mapping only applies │
│ │ │ to UIDs │
├─────┼───────────────┼──────────────────────────┤
│g │ g10000:1000:1 │ The mapping only applies │
│ │ │ to GIDs │
└─────┴───────────────┴──────────────────────────┘

For instance given the command

podman create --gidmap "0:0:1000" --gidmap "g2000:2000:1"

Since no --uidmap is given, the --gidmap is copied to --uidmap, giving a command
equivalent to

podman create --gidmap "0:0:1000" --gidmap "2000:2000:1" --uidmap "0:0:1000"

The --gidmap "g2000:2000:1" used the g flag and therefore it was not copied to --uidmap.

Rootless mapping of additional host GIDs

A rootless user may desire to map a specific host group that has already been subordinated
within /etc/subgid without specifying the rest of the mapping.

This can be done with --gidmap "+gcontainer_gid:@host_gid"

Where:

• The host GID is given through the @ symbol

• The mapping of this GID is not copied over to --usermap thanks to the g flag.

• The rest of the container IDs will be mapped starting from 0 to n, with all the
remaining subordinated GIDs, thanks to the + flag.

For instance, if a user belongs to the group 2000 and that group is subordinated to that
user (with usermod --add-subgids 2000-2000 $USER), the user can map the group into the
container with: --gidmap=+g100000:@2000.

If this mapping is combined with the option, --group-add=keep-groups, the process in the
container will belong to group 100000, and files belonging to group 2000 in the host will
appear as being owned by group 100000 inside the container.

podman run --group-add=keep-groups --gidmap="+g100000:@2000" ...

No subordinate UIDs

Even if a user does not have any subordinate UIDs in /etc/subuid, --uidmap can be used to
map the normal UID of the user to a container UID by running podman create --uidmap
$container_uid:0:1 --user $container_uid ....

Pods

The --uidmap option cannot be called in conjunction with the --pod option as a uidmap
cannot be set on the container level when in a pod.

--ulimit=option
Ulimit options. Sets the ulimits values inside of the container.

--ulimit with a soft and hard limit in the format =[:]. For example:

$ podman run --ulimit nofile=1024:1024 --rm ubi9 ulimit -n 1024

Set -1 for the soft or hard limit to set the limit to the maximum limit of the current
process. In rootful mode this is often unlimited.

Use host to copy the current configuration from the host.

Don't use nproc with the ulimit flag as Linux uses nproc to set the maximum number of
processes available to a user, not to a container.

Use the --pids-limit option to modify the cgroup control to limit the number of processes
within a container.

--umask=umask
Set the umask inside the container. Defaults to 0022. Remote connections use local
containers.conf for defaults

--unsetenv=env
Unset default environment variables for the container. Default environment variables
include variables provided natively by Podman, environment variables configured by the
image, and environment variables from containers.conf.

--unsetenv-all
Unset all default environment variables for the container. Default environment variables
include variables provided natively by Podman, environment variables configured by the
image, and environment variables from containers.conf.

--user, -u=user[:group]
Sets the username or UID used and, optionally, the groupname or GID for the specified
command. Both user and group may be symbolic or numeric.

Without this argument, the command runs as the user specified in the container image.
Unless overridden by a USER command in the Containerfile or by a value passed to this
option, this user generally defaults to root.

When a user namespace is not in use, the UID and GID used within the container and on the
host match. When user namespaces are in use, however, the UID and GID in the container may
correspond to another UID and GID on the host. In rootless containers, for example, a user
namespace is always used, and root in the container by default corresponds to the UID and
GID of the user invoking Podman.

--userns=mode
Set the user namespace mode for the container.

If --userns is not set, the default value is determined as follows. - If --pod is set,
--userns is ignored and the user namespace of the pod is used. - If the environment
variable PODMAN_USERNS is set its value is used. - If userns is specified in
containers.conf this value is used. - Otherwise, --userns=host is assumed.

--userns="" (i.e., an empty string) is an alias for --userns=host.

This option is incompatible with --gidmap, --uidmap, --subuidname and --subgidname.

Rootless user --userns=Key mappings:

┌────────────────────────┬───────────┬──────────────────────────┐
│Key │ Host User │ Container User │
├────────────────────────┼───────────┼──────────────────────────┤
│auto │ $UID │ nil (Host User UID is │
│ │ │ not mapped into │
│ │ │ container.) │
├────────────────────────┼───────────┼──────────────────────────┤
│host │ $UID │ 0 (Default User account │
│ │ │ mapped to root user in │
│ │ │ container.) │
├────────────────────────┼───────────┼──────────────────────────┤
│keep-id │ $UID │ $UID (Map user account │
│ │ │ to same UID within │
│ │ │ container.) │
├────────────────────────┼───────────┼──────────────────────────┤
│keep-id:uid=200,gid=210 │ $UID │ 200:210 (Map user │
│ │ │ account to specified │
│ │ │ UID, GID value within │
│ │ │ container.) │
├────────────────────────┼───────────┼──────────────────────────┤
│nomap │ $UID │ nil (Host User UID is │
│ │ │ not mapped into │
│ │ │ container.) │
└────────────────────────┴───────────┴──────────────────────────┘

Valid mode values are:

auto[:OPTIONS,...]: automatically create a unique user namespace.

• rootful mode: The --userns=auto flag requires that the user name containers be
specified in the /etc/subuid and /etc/subgid files, with an unused range of
subordinate user IDs that Podman containers are allowed to allocate.

Example: containers:2147483647:2147483648.

• rootless mode: The users range from the /etc/subuid and /etc/subgid files will be
used. Note running a single container without using --userns=auto will use the
entire range of UIDs and not allow further subdividing. See subuid(5).

Podman allocates unique ranges of UIDs and GIDs from the containers subordinate user IDs.
The size of the ranges is based on the number of UIDs required in the image. The number of
UIDs and GIDs can be overridden with the size option.

The option --userns=keep-id uses all the subuids and subgids of the user. The option
--userns=nomap uses all the subuids and subgids of the user except the user's own ID.
Using --userns=auto when starting new containers does not work as long as any containers
exist that were started with --userns=keep-id or --userns=nomap.

Valid auto options:

• gidmapping=CONTAINER_GID:HOST_GID:SIZE: to force a GID mapping to be present in
the user namespace.

• size=SIZE: to specify an explicit size for the automatic user namespace. e.g.
--userns=auto:size=8192. If size is not specified, auto estimates a size for the
user namespace.

• uidmapping=CONTAINER_UID:HOST_UID:SIZE: to force a UID mapping to be present in
the user namespace.

The host UID and GID in gidmapping and uidmapping can optionally be prefixed with the @
symbol. In this case, podman will look up the intermediate ID corresponding to host ID
and it will map the found intermediate ID to the container id. For details see --uidmap.

container:id: join the user namespace of the specified container.

host or "" (empty string): run in the user namespace of the caller. The processes running
in the container have the same privileges on the host as any other process launched by the
calling user.

keep-id: creates a user namespace where the current user's UID:GID are mapped to the same
values in the container. For containers created by root, the current mapping is created
into a new user namespace.

Valid keep-id options:

• uid=UID: override the UID inside the container that is used to map the current
user to.

• gid=GID: override the GID inside the container that is used to map the current
user to.

nomap: creates a user namespace where the current rootless user's UID:GID are not mapped
into the container. This option is not allowed for containers created by the root user.

ns:namespace: run the container in the given existing user namespace.

--uts=mode
Set the UTS namespace mode for the container. The following values are supported:

• host: use the host's UTS namespace inside the container.

• private: create a new namespace for the container (default).

• ns:[path]: run the container in the given existing UTS namespace.

• container:[container]: join the UTS namespace of the specified container.

--variant=VARIANT
Use VARIANT instead of the default architecture variant of the container image. Some
images can use multiple variants of the arm architectures, such as arm/v5 and arm/v7.

--volume, -v=[[SOURCE-VOLUME|HOST-DIR:]CONTAINER-DIR[:OPTIONS]]
Create a bind mount. If -v /HOST-DIR:/CONTAINER-DIR is specified, Podman bind mounts
/HOST-DIR from the host into /CONTAINER-DIR in the Podman container. Similarly, -v SOURCE-
VOLUME:/CONTAINER-DIR mounts the named volume from the host into the container. If no such
named volume exists, Podman creates one. If no source is given, the volume is created as
an anonymously named volume with a randomly generated name, and is removed when the
container is removed via the --rm flag or the podman rm --volumes command.

(Note when using the remote client, including Mac and Windows (excluding WSL2) machines,
the volumes are mounted from the remote server, not necessarily the client machine.)

The OPTIONS is a comma-separated list and can be one or more of:

• rw|ro

• z|Z

• [O]

• [U]

• [no]copy

• [no]dev

• [no]exec

• [no]suid

• [r]bind

• [r]shared|[r]slave|[r]private[r]unbindable [1] ⟨#Footnote1⟩

• idmap[=options]

The CONTAINER-DIR must be an absolute path such as /src/docs. The volume is mounted into
the container at this directory.

If a volume source is specified, it must be a path on the host or the name of a named
volume. Host paths are allowed to be absolute or relative; relative paths are resolved
relative to the directory Podman is run in. If the source does not exist, Podman returns
an error. Users must pre-create the source files or directories.

Any source that does not begin with a . or / is treated as the name of a named volume. If
a volume with that name does not exist, it is created. Volumes created with names are not
anonymous, and they are not removed by the --rm option and the podman rm --volumes
command.

Specify multiple -v options to mount one or more volumes into a container.

Write Protected Volume Mounts

Add :ro or :rw option to mount a volume in read-only or read-write mode, respectively. By
default, the volumes are mounted read-write. See examples.

Chowning Volume Mounts

By default, Podman does not change the owner and group of source volume directories
mounted into containers. If a container is created in a new user namespace, the UID and
GID in the container may correspond to another UID and GID on the host.

The :U suffix tells Podman to use the correct host UID and GID based on the UID and GID
within the container, to change recursively the owner and group of the source volume.
Chowning walks the file system under the volume and changes the UID/GID on each file. If
the volume has thousands of inodes, this process takes a long time, delaying the start of
the container.

Warning use with caution since this modifies the host filesystem.

Labeling Volume Mounts

Labeling systems like SELinux require that proper labels are placed on volume content
mounted into a container. Without a label, the security system might prevent the processes
running inside the container from using the content. By default, Podman does not change
the labels set by the OS.

To change a label in the container context, add either of two suffixes :z or :Z to the
volume mount. These suffixes tell Podman to relabel file objects on the shared volumes.
The z option tells Podman that two or more containers share the volume content. As a
result, Podman labels the content with a shared content label. Shared volume labels allow
all containers to read/write content. The Z option tells Podman to label the content with
a private unshared label Only the current container can use a private volume. Relabeling
walks the file system under the volume and changes the label on each file, if the volume
has thousands of inodes, this process takes a long time, delaying the start of the
container. If the volume was previously relabeled with the z option, Podman is optimized
to not relabel a second time. If files are moved into the volume, then the labels can be
manually change with the chcon -Rt container_file_t PATH command.

Note: Do not relabel system files and directories. Relabeling system content might cause
other confined services on the machine to fail. For these types of containers we
recommend disabling SELinux separation. The option --security-opt label=disable disables
SELinux separation for the container. For example if a user wanted to volume mount their
entire home directory into a container, they need to disable SELinux separation.

$ podman create --security-opt label=disable -v $HOME:/home/user fedora touch /home/user/file

Overlay Volume Mounts

The :O flag tells Podman to mount the directory from the host as a temporary storage using
the overlay file system. The container processes can modify content within the mountpoint
which is stored in the container storage in a separate directory. In overlay terms, the
source directory is the lower, and the container storage directory is the upper.
Modifications to the mount point are destroyed when the container finishes executing,
similar to a tmpfs mount point being unmounted.

For advanced users, the overlay option also supports custom non-volatile upperdir and
workdir for the overlay mount. Custom upperdir and workdir can be fully managed by the
users themselves, and Podman does not remove it on lifecycle completion. Example
:O,upperdir=/some/upper,workdir=/some/work

Subsequent executions of the container sees the original source directory content, any
changes from previous container executions no longer exist.

One use case of the overlay mount is sharing the package cache from the host into the
container to allow speeding up builds.

Note: The O flag conflicts with other options listed above.

Content mounted into the container is labeled with the private label. On SELinux systems,
labels in the source directory must be readable by the container label. Usually
containers can read/execute container_share_t and can read/write container_file_t. If
unable to change the labels on a source volume, SELinux container separation must be
disabled for the container to work.

Do not modify the source directory mounted into the container with an overlay mount, it
can cause unexpected failures. Only modify the directory after the container finishes
running.

Mounts propagation

By default, bind-mounted volumes are private. That means any mounts done inside the
container are not visible on the host and vice versa. One can change this behavior by
specifying a volume mount propagation property. When a volume is shared, mounts done
under that volume inside the container are visible on host and vice versa. Making a volume
slave[1] ⟨#Footnote1⟩ enables only one-way mount propagation: mounts done on the host
under that volume are visible inside the container but not the other way around.

To control mount propagation property of a volume one can use the [r]shared, [r]slave,
[r]private or the [r]unbindable propagation flag. Propagation property can be specified
only for bind mounted volumes and not for internal volumes or named volumes. For mount
propagation to work the source mount point (the mount point where source dir is mounted
on) has to have the right propagation properties. For shared volumes, the source mount
point has to be shared. And for slave volumes, the source mount point has to be either
shared or slave. [1] ⟨#Footnote1⟩

To recursively mount a volume and all of its submounts into a container, use the rbind
option. By default the bind option is used, and submounts of the source directory is not
mounted into the container.

Mounting the volume with a copy option tells podman to copy content from the underlying
destination directory onto newly created internal volumes. The copy only happens on the
initial creation of the volume. Content is not copied up when the volume is subsequently
used on different containers. The copy option is ignored on bind mounts and has no effect.

Mounting volumes with the nosuid options means that SUID executables on the volume can not
be used by applications to change their privilege. By default volumes are mounted with
nosuid.

Mounting the volume with the noexec option means that no executables on the volume can be
executed within the container.

Mounting the volume with the nodev option means that no devices on the volume can be used
by processes within the container. By default volumes are mounted with nodev.

If the HOST-DIR is a mount point, then dev, suid, and exec options are ignored by the
kernel.

Use df HOST-DIR to figure out the source mount, then use findmnt -o TARGET,PROPAGATION
source-mount-dir to figure out propagation properties of source mount. If findmnt(1)
utility is not available, then one can look at the mount entry for the source mount point
in /proc/self/mountinfo. Look at the "optional fields" and see if any propagation
properties are specified. In there, shared:N means the mount is shared, master:N means
mount is slave, and if nothing is there, the mount is private. [1] ⟨#Footnote1⟩

To change propagation properties of a mount point, use mount(8) command. For example, if
one wants to bind mount source directory /foo, one can do mount --bind /foo /foo and mount
--make-private --make-shared /foo. This converts /foo into a shared mount point.
Alternatively, one can directly change propagation properties of source mount. Say / is
source mount for /foo, then use mount --make-shared / to convert / into a shared mount.

Note: if the user only has access rights via a group, accessing the volume from inside a
rootless container fails.

Idmapped mount

If idmap is specified, create an idmapped mount to the target user namespace in the
container. The idmap option supports a custom mapping that can be different than the user
namespace used by the container. The mapping can be specified after the idmap option like:
idmap=uids=0-1-10#10-11-10;gids=0-100-10. For each triplet, the first value is the start
of the backing file system IDs that are mapped to the second value on the host. The
length of this mapping is given in the third value. Multiple ranges are separated with #.

Use the --group-add keep-groups option to pass the user's supplementary group access into
the container.

--volumes-from=CONTAINER[:OPTIONS]
Mount volumes from the specified container(s). Used to share volumes between containers.
The options is a comma-separated list with the following available elements:

• rw|ro

• z

Mounts already mounted volumes from a source container onto another container. CONTAINER
may be a name or ID. To share a volume, use the --volumes-from option when running the
target container. Volumes can be shared even if the source container is not running.

By default, Podman mounts the volumes in the same mode (read-write or read-only) as it is
mounted in the source container. This can be changed by adding a ro or rw option.

To change a label in the container context, add z to the volume mount. This suffix tells
Podman to relabel file objects on the shared volumes. The z option tells Podman that two
entities share the volume content. As a result, Podman labels the content with a shared
content label. Shared volume labels allow all containers to read/write content.

If the location of the volume from the source container overlaps with data residing on a
target container, then the volume hides that data on the target.

--workdir, -w=dir
Working directory inside the container.

The default working directory for running binaries within a container is the root
directory (/). The image developer can set a different default with the WORKDIR
instruction. The operator can override the working directory by using the -w option.

EXAMPLES

       Create a container using a local image:

       $ podman create alpine ls

       Create a container using a local image and annotate it:

       $ podman create --annotation HELLO=WORLD alpine ls

       Create  a  container  using a local image, allocating a pseudo-TTY, keeping stdin open and
       name it myctr:

         podman create -t -i --name myctr alpine ls

       Running a container in a new user namespace requires a mapping of the UIDs and  GIDs  from
       the host:

       $ podman create --uidmap 0:30000:7000 --gidmap 0:30000:7000 fedora echo hello

       Setting automatic user-namespace separated containers:

       # podman create --userns=auto:size=65536 ubi8-init

       Configure the timezone in a container:

       $ podman create --tz=local alpine date
       $ podman create --tz=Asia/Shanghai alpine date
       $ podman create --tz=US/Eastern alpine date

       Ensure   the   first  container  (container1)  is  running  before  the  second  container
       (container2) is started:

       $ podman create --name container1 -t -i fedora bash
       $ podman create --name container2 --requires container1 -t -i fedora bash
       $ podman start --attach container2

       Create a container which requires multiple containers:

       $ podman create --name container1 -t -i fedora bash
       $ podman create --name container2 -t -i fedora bash
       $ podman create --name container3 --requires container1,container2 -t -i fedora bash
       $ podman start --attach container3

       Expose shared libraries inside of container as read-only using a glob:

       $ podman create --mount type=glob,src=/usr/lib64/libnvidia\*,ro -i -t fedora /bin/bash

       Create a container allowing supplemental groups to have access to the volume:

       $ podman create -v /var/lib/design:/var/lib/design --group-add keep-groups ubi8

       Configure execution domain for containers using the personality option:

       $ podman create --name container1 --personality=LINUX32 fedora bash

       Create a container with external rootfs mounted as an overlay:

       $ podman create --name container1 --rootfs /path/to/rootfs:O bash

       Create a container connected to two networks (called net1 and net2) with a static ip:

       $ podman create --network net1:ip=10.89.1.5 --network net2:ip=10.89.10.10 alpine ip addr

   Rootless Containers
       Podman runs as a non-root user on most systems. This feature requires that  a  new  enough
       version  of shadow-utils be installed. The shadow-utils package must include the newuidmap
       and newgidmap executables.

       In order for users to run  rootless,  there  must  be  an  entry  for  their  username  in
       /etc/subuid and /etc/subgid which lists the UIDs for their user namespace.

       Rootless Podman works better if the fuse-overlayfs and slirp4netns packages are installed.
       The fuse-overlayfs package provides a userspace overlay storage  driver,  otherwise  users
       need  to use the vfs storage driver, which can be disk space expensive and less performant
       than other drivers.

       To enable VPN on the container, slirp4netns  or  pasta  needs  to  be  specified;  without
       either, containers need to be run with the --network=host flag.

ENVIRONMENT

       Environment variables within containers can be set using multiple different options:  This
       section describes the precedence.

       Precedence order (later entries override earlier entries):

              • --env-host : Host environment of the process executing Podman is added.

              • --http-proxy: By default, several environment variables are passed  in  from  the
                host, such as http_proxy and no_proxy. See --http-proxy for details.

              • Container image : Any environment variables specified in the container image.

              • --env-file : Any environment variables specified via env-files. If multiple files
                specified, then they override each other in order of entry.

              • --env : Any environment variables specified overrides previous settings.

       Create containers and  set  the  environment  ending  with  a  *.   The  trailing  *  glob
       functionality is only active when no value is specified:

       $ export ENV1=a
       $ podman create --name ctr1 --env 'ENV*' alpine env
       $ podman start --attach ctr1 | grep ENV
       ENV1=a
       $ podman create --name ctr2 --env 'ENV*=b' alpine env
       $ podman start --attach ctr2 | grep ENV
       ENV*=b

CONMON

       When  Podman  starts  a  container  it  actually  executes  the conmon program, which then
       executes the OCI Runtime.  Conmon is the container monitor.  It is a small  program  whose
       job  is to watch the primary process of the container, and if the container dies, save the
       exit code.  It also holds open the tty of the container, so that it  can  be  attached  to
       later.  This  is  what allows Podman to run in detached mode (backgrounded), so Podman can
       exit but conmon continues to run.  Each container has their own instance of conmon. Conmon
       waits  for  the  container  to  exit, gathers and saves the exit code, and then launches a
       Podman process to complete the  container  cleanup,  by  shutting  down  the  network  and
       storage.   For more information about conmon, see the conmon(8) man page.

FILES

       /etc/subuid /etc/subgid

       NOTE:  Use  the  environment  variable  TMPDIR to change the temporary storage location of
       downloaded container images. Podman defaults to use /var/tmp.

HISTORY

       October  2017,  converted  from  Docker  documentation  to  Podman by Dan Walsh for Podman
       <dwalsh@redhat.com>

       November 2014, updated by Sven Dowideit <SvenDowideit@home.org.au>

       September 2014, updated by Sven Dowideit <SvenDowideit@home.org.au>

       August 2014, updated by Sven Dowideit <SvenDowideit@home.org.au>

FOOTNOTES

       1: The Podman project is committed to inclusivity, a core value of open source. The master
       and  slave  mount propagation terminology used here is problematic and divisive, and needs
       to be changed. However, these terms are currently used within the Linux kernel and must be
       used  as-is  at  this  time.  When  the kernel maintainers rectify this usage, Podman will
       follow suit immediately.

                                                                                 podman-create(1)

NAME

SYNOPSIS

DESCRIPTION

IMAGE

OPTIONS

EXAMPLES

ENVIRONMENT

CONMON

FILES

SEE ALSO

HISTORY

FOOTNOTES