Provided by: podman_3.4.4+ds1-1ubuntu1.22.04.2_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. You can then 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 will be used by default. For remote Podman, 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 will be queried to find a
matching image. By default, credentials from podman login (stored at
$XDG_RUNTIME_DIR/containers/auth.json by default) will be 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
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.
--annotation=key=value
Add an annotation to the container. The format is key=value. The --annotation option can
be set multiple times.
--arch=ARCH
Override the architecture, defaults to hosts, of the image to be pulled. For example, arm.
--attach, -a=location
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 standard 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
Note: You can also override the default path of the authentication file by setting the
REGISTRY_AUTH_FILE environment variable. export REGISTRY_AUTH_FILE=path
--blkio-weight=weight
Block IO weight (relative weight) accepts a weight value between 10 and 1000.
--blkio-weight-device=weight
Block IO weight (relative device weight, format: DEVICE_NAME:WEIGHT).
--cap-add=capability
Add Linux capabilities
--cap-drop=capability
Drop Linux capabilities
--cgroupns=mode
Set the cgroup namespace mode for the container.
host: use the host's cgroup namespace inside the container.
container:<NAME|ID>: join the namespace of the specified container.
ns:<PATH>: join the namespace at the specified path.
private: create a new cgroup namespace.
If the host uses cgroups v1, the default is set to host. On cgroups v2 the default is
private.
--cgroups=mode
Determines whether the container will create CGroups. Valid values are enabled, disabled,
no-conmon, split, which the default being enabled.
The enabled option will create a new cgroup under the cgroup-parent. The disabled option
will force 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.
--cgroup-parent=path
Path to cgroups under which the cgroup for the container will be created. If the path is
not absolute, the path is considered to be relative to the cgroups path of the init
process. Cgroups will be created if they do not already exist.
--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.
--cidfile=id
Write the container ID to the file
--conmon-pidfile=path
Write the pid of the conmon process to a file. conmon runs in a separate process than
Podman, so this is necessary when using systemd to restart Podman containers. (This
option is not available with the remote Podman client)
--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 CPU limits may not be allowed for non-root users. For more
details, see
https://github.com/containers/podman/blob/master/troubleshooting.md#26-running-containers-
with-cpu-limits-fails-with-a-permissions-error
--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 you provide a number, the container will be
allowed to use that much CPU time until the CPU period ends (controllable via --cpu-
period).
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/master/troubleshooting.md#26-running-containers-
with-cpu-limits-fails-with-a-permissions-error
--cpu-rt-period=microseconds
Limit the CPU real-time period in microseconds
Limit the container's Real Time CPU usage. This flag tell the kernel to restrict the
container's Real Time CPU usage to the period you specify.
This flag is not supported on cgroups V2 systems.
--cpu-rt-runtime=microseconds
Limit the CPU real-time runtime in microseconds
Limit the containers Real Time CPU usage. This flag 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 could 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 flag is not supported on cgroups V2 systems.
--cpu-shares=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 weighting of all
other running containers.
To modify the proportion from the default of 1024, use the --cpu-shares flag to set the
weighting to 2 or higher.
The proportion will only apply 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 will vary 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 would receive 50% of the total CPU time. If you add a fourth
container 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 you start one container {C0}
with -c=512 running one process, and another container {C1} with -c=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
--cpus=number
Number of CPUs. The default is 0.0 which means no limit. This is shorthand for --cpu-
period and --cpu-quota, so you may only set either
--cpus or --cpu-period and --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/master/troubleshooting.md#26-running-containers-
with-cpu-limits-fails-with-a-permissions-error
--cpuset-cpus=cpus
CPUs in which to allow execution (0-3, 0,1)
--cpuset-mems=nodes
Memory nodes (MEMs) in which to allow execution (0-3, 0,1). Only effective on NUMA
systems.
If you have four memory nodes on your system (0-3), use --cpuset-mems=0,1 then processes
in your container will only use memory from the first two memory nodes.
--device=host-device[:container-device][:permissions]
Add a host device to the container. Optional permissions parameter can be used to specify
device permissions, it is combination of r for read, w for write, and m for mknod(2).
Example: --device=/dev/sdc:/dev/xvdc:rwm.
Note: if _hostdevice is a symbolic link then it will be resolved first. The container
will only store the major and minor numbers of the host device.
Note: if the user only has access rights via a group, accessing the device from inside a
rootless container will fail. Use the --group-add keep-groups flag to pass the user's
supplementary group access into the container.
Podman may load kernel modules required for using the specified device. The devices that
podman will load modules when necessary are: /dev/fuse.
--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 (Documentation/cgroup-v1/devices.txt):
- 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
Limit read rate (bytes per second) from a device (e.g. --device-read-bps=/dev/sda:1mb)
--device-read-iops=path
Limit read rate (IO per second) from a device (e.g. --device-read-iops=/dev/sda:1000)
--device-write-bps=path
Limit write rate (bytes per second) to a device (e.g. --device-write-bps=/dev/sda:1mb)
--device-write-iops=path
Limit write rate (IO per second) to a device (e.g. --device-write-iops=/dev/sda:1000)
--disable-content-trust
This is a Docker specific option to disable image verification to a Docker registry and is
not supported by Podman. This flag is a NOOP and provided solely for scripting
compatibility.
--dns=dns
Set custom DNS servers. Invalid if using --dns and --network that is set to 'none' or
container:<name|id>.
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 flags 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 will be used without changes.
--dns-opt=option
Set custom DNS options. Invalid if using --dns-opt and --network that is set to 'none' or
container:<name|id>.
--dns-search=domain
Set custom DNS search domains. Invalid if using --dns-search and --network that is set to
'none' or container:<name|id>. (Use --dns-search=. if you don't wish to set the search
domain)
--entrypoint="command" | '["command", arg1 , ...]'
Overwrite the default ENTRYPOINT of the image
This option allows you to overwrite the default entrypoint of 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, so that when you set an ENTRYPOINT you can run
the container as if it were that binary, complete with default options, and you can pass
in more options via the COMMAND. But, sometimes an operator may want to run something else
inside the container, so you can override the default ENTRYPOINT at runtime by using a
--entrypoint and a string to specify the new ENTRYPOINT.
You need to 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 will check the host environment for a value and set the variable only if it
is set on the host. If an environment variable ending in * is specified, Podman will
search the host environment for variables starting with the prefix and will add those
variables to the container. If an environment variable with a trailing ***** is specified,
then a value must be supplied.
See Environment ⟨#environment⟩ note below for precedence and examples.
--env-host=true|false
Use host environment inside of the container. See Environment note below for precedence.
(This option is not available with the remote Podman client)
--env-file=file
Read in a line delimited file of environment variables. See Environment note below for
precedence.
--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=container_gid:host_gid:amount
GID map for the user namespace. Using this flag will run the container with user namespace
enabled. It conflicts with the --userns and --subgidname flags.
The following example maps uids 0-2000 in the container to the uids 30000-31999 on the
host and gids 0-2000 in the container to the gids 30000-31999 on the host.
--gidmap=0:30000:2000
--group-add=group|keep-groups
Add additional groups to assign to 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, you cannot add any other groups with this flag. (Not
available for remote commands)
--health-cmd="command" | '["command", arg1 , ...]'
Set or alter a healthcheck command for a container. The command is a command to be
executed inside your container that determines your 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 will be
interpreted as an argument to /bin/sh -c.
--health-interval=interval
Set an interval for the healthchecks (a value of disable results in no automatic timer
setup) (default "30s")
--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
--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.
--hostname=name, -h
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 will be used.
--help
Print usage statement
--http-proxy=true|false
By default proxy environment variables are passed into the container if set for the Podman
process. This can be disabled by setting the --http-proxy option 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 should not use any proxy. Proxy environment variables specified
for the container in any other way will override the values that would 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.) (This option is not available with the remote Podman client)
For example, to disable passing these environment variables from host to container:
--http-proxy=false
Defaults to true
--image-volume, builtin-volume=bind|tmpfs|ignore
Tells Podman how to handle the builtin image volumes. Default is bind.
• bind: An anonymous named volume will be 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.
--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
will run with each and every pod start, whereas the once value means the container will
only run once when the pod is started and then the container is removed.
Init containers are only run on pod start. Restarting a pod will not execute any init
containers should they be present. 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=true|false
Keep STDIN open even if not attached. The default is false.
--ip6=ip
Not implemented
--ip=ip
Specify a static IP 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 CNI network's IP address pool (default 10.88.0.0/16).
--ipc=ipc
Default is to create a private IPC namespace (POSIX SysV IPC) for the container
container:<name|id>: reuses another container shared memory, semaphores and
message queues host: use the host 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. ns:<path> path to an IPC namespace
to join.
--kernel-memory=number[unit]
Kernel memory limit (format: <number>[<unit>], where unit = b (bytes), k (kilobytes), m
(megabytes), or g (gigabytes))
Constrains the kernel memory available to a container. If a limit of 0 is specified (not
using --kernel-memory), the container's kernel memory is not limited. If you specify a
limit, it may be rounded up to a multiple of the operating system's page size and the
value can be very large, millions of trillions.
This flag is not supported on cgroups V2 systems.
--label, -l=label
Add metadata to a container (e.g., --label com.example.key=value)
--label-file=file
Read in a line delimited file of labels
--link-local-ip=ip
Not implemented
--log-driver="k8s-file"
Logging driver for the container. Currently available options are k8s-file, journald, and
none, with json-file aliased to k8s-file for scripting compatibility.
--log-opt=name=value
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.
--log-opt tag="{{.ImageName}}"
It supports the same keys as podman inspect --format.
It is currently supported only by the journald log driver.
--mac-address=address
Container MAC address (e.g. 92:d0:c6:0a:29:33)
Remember that the MAC address in an Ethernet network must be unique. The IPv6 link-local
address will be based on the device's MAC address according to RFC4862.
--memory, -m=limit
Memory limit (format: <number>[<unit>], where unit = b (bytes), k (kilobytes), m
(megabytes), or g (gigabytes))
Allows you to constrain the memory available to a container. 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 would be very
large, that's millions of trillions).
--memory-reservation=limit
Memory soft limit (format: <number>[<unit>], where unit = b (bytes), k (kilobytes), m
(megabytes), or g (gigabytes))
After setting memory reservation, when the system detects memory contention or low memory,
containers are forced to restrict their consumption to their reservation. So you should
always set the value below --memory, otherwise the hard limit will take precedence. By
default, memory reservation will be the same as memory limit.
--memory-swap=limit
A limit value equal to memory plus swap. Must be used with the -m (--memory) flag. The
swap LIMIT should always be larger than -m (--memory) value. By default, the swap LIMIT
will be set to double the value of --memory.
The format of LIMIT is <number>[<unit>]. Unit can be b (bytes), k (kilobytes), m
(megabytes), or g (gigabytes). If you don't specify a unit, b is used. Set LIMIT to -1 to
enable unlimited swap.
--memory-swappiness=number
Tune a container's memory swappiness behavior. Accepts an integer between 0 and 100.
This flag is not supported on cgroups V2 systems.
--mount=type=TYPE,TYPE-SPECIFIC-OPTION[,...]
Attach a filesystem mount to the container
Current supported mount TYPEs are bind, volume, image, tmpfs and devpts. [1] ⟨#Footnote1⟩
e.g.
type=bind,source=/path/on/host,destination=/path/in/container
type=bind,src=/path/on/host,dst=/path/in/container,relabel=shared
type=volume,source=vol1,destination=/path/in/container,ro=true
type=tmpfs,tmpfs-size=512M,destination=/path/in/container
type=image,source=fedora,destination=/fedora-image,rw=true
type=devpts,destination=/dev/pts
Common Options:
· src, source: mount source spec for bind and volume. Mandatory for bind.
· dst, destination, target: mount destination spec.
Options specific to volume:
· ro, readonly: true or false (default).
Options specific to image:
· rw, readwrite: true or false (default).
Options specific to bind:
· ro, readonly: true or false (default).
· bind-propagation: shared, slave, private, unbindable, rshared, rslave, runbindable, or rprivate(default). See also mount(2).
. bind-nonrecursive: do not setup a recursive bind mount. By default it is recursive.
. relabel: shared, private.
Options specific to tmpfs:
· ro, readonly: true or false (default).
· tmpfs-size: Size of the tmpfs mount in bytes. Unlimited by default in Linux.
· tmpfs-mode: File mode of the tmpfs in octal. (e.g. 700 or 0700.) Defaults to 1777 in Linux.
· tmpcopyup: Enable copyup from the image directory at the same location to the tmpfs. Used by default.
· notmpcopyup: Disable copying files from the image to the tmpfs.
--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 will generate a random string name. The name is useful any place you
need to identify a container. This works for both background and foreground containers.
--network=mode, --net
Set the network mode for the container. Invalid if using --dns, --dns-opt, or --dns-search
with --network that is set to none or container:id. If used together with --pod, the
container will not join the pod's network namespace.
Valid mode values are:
• bridge: Create a network stack on the default bridge. This is the default for
rootfull containers.
• 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 will use 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.
• network: Connect to a user-defined network, multiple networks should be comma-
separated.
• ns:path: Path to a network namespace to join.
• private: Create a new namespace for the container. This will use the bridge mode
for rootfull 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:
• allow_host_loopback=true|false: Allow the slirp4netns to reach the host
loopback IP (10.0.2.2, which is added to /etc/hosts as host.containers.internal
for your convenience). 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 false. (Required for
outbound_addr6).
• outbound_addr=INTERFACE: Specify the outbound interface slirp should bind to
(ipv4 traffic only).
• outbound_addr=IPv4: Specify the outbound ipv4 address slirp should bind to.
• outbound_addr6=INTERFACE: Specify the outbound interface slirp should bind to
(ipv6 traffic only).
• outbound_addr6=IPv6: Specify the outbound ipv6 address slirp should bind to.
• port_handler=rootlesskit: Use rootlesskit for port forwarding. Default. Note:
Rootlesskit changes the source IP address of incoming packets to a IP address
in the container network namespace, usually 10.0.2.100. If your 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.
--network-alias=alias
Add network-scoped alias for the container. NOTE: A container will only have access to
aliases on the first network that it joins. This is a limitation that will be removed in a
later release.
--no-healthcheck=true|false
Disable any defined healthchecks for container.
--no-hosts=true|false
Do not create /etc/hosts for the container. By default, Podman will manage /etc/hosts,
adding the container's own IP address and any hosts from --add-host.
--no-hosts disables this, and the image's /etc/host will be preserved unmodified.
This option conflicts with --add-host.
--oom-kill-disable=true|false
Whether to disable OOM Killer for the container or not.
--oom-score-adj=num
Tune the host's OOM preferences for containers (accepts -1000 to 1000)
--os=OS
Override the OS, defaults to hosts, of the image to be pulled. For example, windows.
--personality=persona
Personality sets the execution domain via Linux personality(2).
--pid=pid
Set the PID mode for the container Default is to create a private PID namespace for the
container - container:<name|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: join the specified PID
namespace - private: create a new namespace for the container (default)
--pids-limit=limit
Tune the container's pids limit. Set -1 to have unlimited pids for the container. (default
"4096" on systems that support PIDS cgroups).
--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.
--pod=name
Run container in an existing pod. If you want Podman to make the pod for you, preference
the pod name with new:. To make a pod with more granular options, use the podman pod
create command before creating a container.
--pod-id-file=path
Run container in an existing pod and read the pod's ID from the specified file. If a
container is run within a pod, and the pod has an infra-container, the infra-container
will be started before the container is.
--privileged=true|false
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 not allowed to
access any devices. A “privileged” container is given access to all devices.
When the operator executes a privileged container, Podman enables access to all devices on
the host, turns off graphdriver mount options, as well as turning off most of the security
measures protecting the host from the container.
Rootless containers cannot have more privileges than the account that launched them.
--publish, -p=port
Publish a container's port, or range of ports, to the host
Format: ip:hostPort:containerPort | ip::containerPort | hostPort:containerPort |
containerPort 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. (e.g., podman run -p 1234-1236:1222-1224 --name
thisWorks -t busybox but not podman run -p 1230-1236:1230-1240 --name
RangeContainerPortsBiggerThanRangeHostPorts -t busybox) With host IP: podman run -p
127.0.0.1:$HOSTPORT:$CONTAINERPORT --name CONTAINER -t someimage If host IP is set to
0.0.0.0 or not set at all, the port will be bound on all IPs on the host. 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 will be randomly assigned a port on the host. Use podman port to see the actual
mapping: podman port CONTAINER $CONTAINERPORT
Note: if a container will be run 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 - you have 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=true|false
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. The default is false.
If the operator uses -P (or -p) then Podman will make the exposed port accessible on the
host and the ports will be available to any client that can reach the host. When using -P,
Podman will bind 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=missing
Pull image before creating ("always"|"missing"|"never") (default "missing").
'missing': default value, attempt to pull the latest image from the registries
listed in registries.conf if a local image does not exist.Raise an error if the image is
not in any listed registry and is not present locally.
'always': Pull the image from the first registry it is found in as listed in
registries.conf. Raise an error if not found in the registries, even if the image is
present locally.
'never': do not pull the image from the registry, use only the local version. Raise
an error if the image is not present locally.
Defaults to missing.
--quiet, -q
Suppress output information when pulling images
--read-only=true|false
Mount the container's root filesystem as read only.
By default a container will have its root filesystem writable allowing processes to write
files anywhere. By specifying the --read-only flag the container will have its root
filesystem mounted as read only prohibiting any writes.
--read-only-tmpfs=true|false
If container is running in --read-only mode, then mount a read-write tmpfs on /run, /tmp,
and /var/tmp. The default is true
--replace=true|false
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 will be
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 will not take effect if a
container is stopped via the podman kill or podman stop commands.
Valid values are:
• no : Do not restart containers on exit
• on-failure[:max_retries] : Restart containers when they exit with a non-0 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
Please note that restart will not restart containers after a system reboot. If this
functionality is required in your environment, you can invoke Podman from a systemd unit
file, or create an init script for whichever init system is in use. To generate systemd
unit files, please see podman generate systemd
--rm=true|false
Automatically remove 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.
--sdnotify=container|conmon|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 will set 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 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 should not use it.
--seccomp-policy=policy
Specify the policy to select the seccomp profile. If set to image, Podman will look for a
"io.containers.seccomp.profile" label in the container-image config and use its value as a
seccomp profile. Otherwise, Podman will follow 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 should not be
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
will be 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 will not affect the secret inside the container.
Secrets and its storage are managed using the podman secret command.
Secret Options
• type=mount|env : How the secret will be exposed to the container. Default
mount.
• target=target : Target of secret. Defaults to secret name.
• 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.
--security-opt=option
Security Options
• apparmor=unconfined : Turn off apparmor confinement for the container
• apparmor=your-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.
• 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 : White listed syscalls seccomp Json file to be used as a
seccomp filter
• 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 will unmask 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. 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 (/etc/containers/containers.conf or
$HOME/.config/containers/containers.conf) file.
--shm-size=size
Size of /dev/shm (format: <number>[<unit>], where unit = b (bytes), k (kilobytes), m
(megabytes), or g (gigabytes)) If you omit the unit, the system uses bytes. If you omit
the size entirely, the system uses 64m. When size is 0, there is no limit on the amount
of memory used for IPC by the container.
--stop-signal=SIGTERM
Signal to stop a container. Default is SIGTERM.
--stop-timeout=seconds
Timeout (in seconds) to stop a container. Default is 10. Remote connections use local
containers.conf for defaults
--subgidname=name
Name for GID map from the /etc/subgid file. Using this flag will run the container with
user namespace enabled. This flag conflicts with --userns and --gidmap.
--subuidname=name
Name for UID map from the /etc/subuid file. Using this flag will run the container with
user namespace enabled. This flag conflicts with --userns and --uidmap.
--sysctl=SYSCTL
Configure namespaced kernel parameters at runtime
IPC Namespace - current sysctls 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 you use the --ipc=host option these sysctls will not be allowed.
Network Namespace - current sysctls allowed:
Sysctls beginning with net.*
Note: if you use the --network=host option these sysctls will not be allowed.
--systemd=true|false|always
Run container in systemd mode. The default is true.
The value always enforces the systemd mode is enforced without looking at the executable
name. Otherwise, if set to true and the command you are running inside the container is
systemd, /usr/sbin/init, /sbin/init or /usr/local/sbin/init.
If the command you are running inside of the container is systemd, Podman will setup tmpfs
mount points in the following directories:
/run, /run/lock, /tmp, /sys/fs/cgroup/systemd, /var/lib/journal
It will also set the default stop signal to SIGRTMIN+3.
This allow systemd to run in a confined container without any modifications.
Note: 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 will run until they exit or are stopped by podman stop.
--tls-verify=true|false
Require HTTPS and verify certificates when contacting registries (default: true). If
explicitly set to true, then TLS verification will be used. If set to false, then TLS
verification will not be used. If not specified, TLS verification will be used unless the
target registry is listed as an insecure registry in registries.conf.
--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 you do not specify any options, the systems
uses the following options: rw,noexec,nosuid,nodev.
--tty, -t=true|false
Allocate a pseudo-TTY. The default is false.
When set to true Podman will allocate a pseudo-tty and attach to the standard input of the
container. This can be used, for example, to run a throwaway interactive shell. The
default is false.
Note: The -t option is incompatible with a redirection of the Podman client standard
input.
--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
--umask=umask
Set the umask inside the container. Defaults to 0022. Remote connections use local
containers.conf for defaults
--uidmap=container_uid:from_uid:amount
Run the container in a new user namespace using the supplied 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 _fromuid value is based upon the user running the command, either rootfull or rootless
users. * rootfull user: container_uid:host_uid:amount * rootless user:
container_uid:intermediate_uid:amount
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 will be mapped. If for example
amount is 4 the mapping would look like:
| host UID | container UID | | - | - | |
_fromuid | _containeruid | | _fromuid + 1 | _containeruid + 1 | | _fromuid + 2 |
_containeruid + 2 | | _fromuid + 3 | _containeruid + 3 |
When podman create is called by an unprivileged user (i.e. running rootless), the value
_fromuid 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 the user starting Podman | 0
| | 1st subordinate UID for the user starting Podman | 1 | | 2nd
subordinate UID for the user starting Podman | 2 | | 3rd subordinate UID
for the user starting Podman | 3 | | nth subordinate UID for the user
starting Podman | 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 would look like:
| intermediate UID | container UID | | - | -
| | _fromuid | _containeruid | | _fromuid + 1 | _containeruid + 1 | |
_fromuid + 2 | _containeruid + 2 | | _fromuid + 3 | _containeruid + 3 | |
_fromuid + 4 | _containeruid + 4 |
Even if a user does not have any subordinate UIDs in /etc/subuid, --uidmap could still 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 ....
--ulimit=option
Ulimit options
You can pass host to copy the current configuration from the host.
--user, -u=user
Sets the username or UID used and optionally the groupname or GID for the specified
command.
The following examples are all valid: --user [user | user:group | uid | uid:gid | user:gid
| uid:group ]
Without this argument the command will be run as root in the container.
--userns=mode
Set the user namespace mode for the container. It defaults to the PODMAN_USERNS
environment variable. An empty value ("") means user namespaces are disabled unless an
explicit mapping is set with the --uidmap and --gidmap options.
Valid mode values are:
auto[:OPTIONS,...]: automatically create a unique user namespace.
The --userns=auto flag, requires that the user name containers and a range of subordinate
user ids that the Podman container is allowed to use be specified in the /etc/subuid and
/etc/subgid files.
Example: containers:2147483647:2147483648.
Podman allocates unique ranges of UIDs and GIDs from the containers subpordinate 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 auto options currently does not
work in rootless mode
Valid auto options:
• gidmapping=_CONTAINER_GID:HOSTGID: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 will estimate a size for
the user namespace.
• uidmapping=_CONTAINER_UID:HOSTUID:SIZE: to force a UID mapping to be present in
the user namespace.
container:id: join the user namespace of the specified container.
host: run in the user namespace of the caller. The processes running in the container will
have the same privileges on the host as any other process launched by the calling user
(default).
keep-id: creates a user namespace where the current rootless user's UID:GID are mapped to
the same values in the container. This option is ignored for containers created by the
root user.
ns:namespace: run the container in the given existing user namespace.
private: create a new namespace for the container.
This option is incompatible with --gidmap, --uidmap, --subuidname and --subgidname.
--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 you specify, -v /HOST-DIR:/CONTAINER-DIR, Podman bind mounts
/HOST-DIR in the host to /CONTAINER-DIR in the Podman container. Similarly, -v SOURCE-
VOLUME:/CONTAINER-DIR will mount the volume in the host to the container. If no such named
volume exists, Podman will create one. The OPTIONS are a comma-separated list and can be:
[1] ⟨#Footnote1⟩ (Note when using the remote client, the volumes will be mounted from the
remote server, not necessarily the client machine.)
The options is a comma-separated list and can be:
• rw|ro
• z|Z
• [r]shared|[r]slave|[r]private[r]unbindable
• [r]bind
• [no]exec
• [no]dev
• [no]suid
• [O]
• [U]
The CONTAINER-DIR must be an absolute path such as /src/docs. The volume will be mounted
into the container at this directory.
Volumes may specify a source as well, as either a directory on the host or the name of a
named volume. If no source is given, the volume will be created as an anonymously named
volume with a randomly generated name, and will be removed when the container is removed
via the --rm flag or podman rm --volumes.
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 will
return an error. Users must pre-create the source files or directories.
Any source that does not begin with a . or / will be treated as the name of a named
volume. If a volume with that name does not exist, it will be created. Volumes created
with names are not anonymous, and they are not removed by the --rm option and the podman
rm --volumes command.
You can specify multiple -v options to mount one or more volumes into a container.
Write Protected Volume Mounts
You can add :ro or :rw suffix to a volume to mount it 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.
Warning use with caution since this will modify 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, you can 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 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.
Note: Do not relabel system files and directories. Relabeling system content might cause
other confined services on your machine to fail. For these types of containers we
recommend that disable SELinux separation. The option --security-opt label=disable
disables SELinux separation for containers used in the build. 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 will be the lower, and the container storage directory will be the upper.
Modifications to the mount point are destroyed when the container finishes executing,
similar to a tmpfs mount point being unmounted.
Subsequent executions of the container will see 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 you cannot change the labels on a source volume, SELinux container
separation must be disabled for the container to work.
- The source directory mounted into the container with an overlay mount should not be
modified, it can cause unexpected failures. It is recommended that you do not modify the
directory until the container finishes running.
Mounts propagation
By default bind mounted volumes are private. That means any mounts done inside container
will not be visible on host and vice versa. One can change this behavior by specifying a
volume mount propagation property. Making a volume shared mounts done under that volume
inside container will be visible on host and vice versa. Making a volume slave enables
only one way mount propagation and that is mounts done on host under that volume will be
visible inside container but not the other way around. [1] ⟨#Footnote1⟩
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⟩
If you want to recursively mount a volume and all of its submounts into a container, then
you can use the rbind option. By default the bind option is used, and submounts of the
source directory will not be mounted into the container.
Mounting the volume with the nosuid options means that SUID applications on the volume
will not be able 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 will be
able to executed within the container.
Mounting the volume with the nodev option means that no devices on the volume will be able
to be used by processes within the container. By default volumes are mounted with nodev.
If the <source-dir> is a mount point, then "dev", "suid", and "exec" options are ignored
by the kernel.
Use df <source-dir> to figure out the source mount and then use findmnt -o
TARGET,PROPAGATION <source-mount-dir> to figure out propagation properties of source
mount. If findmnt utility is not available, then one can look at mount entry for source
mount point in /proc/self/mountinfo. Look at optional fields and see if any propagation
properties are specified. shared:X means mount is shared, master:X means mount is slave
and if nothing is there that means mount is private. [1] ⟨#Footnote1⟩
To change propagation properties of a mount point use mount 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 will convert /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 will fail. Use the --group-add keep-groups flag 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. You must
supply the source's container-id or container-name. To share a volume, use the --volumes-
from option when running the target container. You can share volumes 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. You can change this by adding a ro or rw option.
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, you can 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 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.
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.
--pidfile=path
When the pidfile location is specified, the container process' PID will be written to the
pidfile. (This option is not available with the remote Podman client) If the pidfile
option is not specified, the container process' PID will be 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
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
Set UID/GID mapping in a new user namespace
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 timezone in a container
$ podman create --tz=local alpine date
$ podman create --tz=Asia/Shanghai alpine date
$ podman create --tz=US/Eastern alpine date
Adding dependency containers
Podman will make sure 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
Multiple containers can be required.
$ 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
Configure keep supplemental groups for access to volume
$ podman create -v /var/lib/design:/var/lib/design --group-add keep-groups ubi8
Configure execution domain for containers using personality flag
$ podman create --name container1 --personaity=LINUX32 fedora bash
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.
Note: RHEL7 and Centos 7 will not have this feature until RHEL7.7 is released.
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 is diskspace expensive and does not perform
well. slirp4netns is required for VPN, without it 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 will be 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 will override previous settings.
Create containers and set the environment ending with a * and a *****
$ export ENV1=a
$ podman create --name ctr --env ENV* alpine printenv ENV1
$ podman start --attach ctr
a
$ podman create --name ctr --env ENV*****=b alpine printenv ENV*****
$ podman start --attach ctr
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 on conmon, please reference 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.
SEE ALSO
podman(1), podman-secret(1), podman-save(1), podman-ps(1), podman-attach(1), podman-pod-
create(1), podman-port(1), *podman-start(1), podman-kill(1), podman-stop(1), podman-
generate-systemd(1) podman-rm(1), subgid(5), subuid(5), containers.conf(5),
systemd.unit(5), setsebool(8), slirp4netns(1), fuse-overlayfs(1), proc(5), conmon(8),
personality(2).
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 should
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)()