Provided by: podman_4.9.3+ds1-1ubuntu0.1_amd64 bug

NAME

       podman-build - Build a container image using a Containerfile

SYNOPSIS

       podman build [options] [context]

       podman image build [options] [context]

DESCRIPTION

       podman  build  Builds  an  image  using  instructions  from  one or more Containerfiles or
       Dockerfiles and a specified build context directory. A Containerfile uses the same  syntax
       as  a  Dockerfile internally. For this document, a file referred to as a Containerfile can
       be a file named either 'Containerfile' or 'Dockerfile'.

       The build context directory can be specified  as  the  http(s)  URL  of  an  archive,  git
       repository or Containerfile.

       When  invoked  with  -f and a path to a Containerfile, with no explicit CONTEXT directory,
       Podman uses the Containerfile's parent directory as its build context.

       Containerfiles ending with a ".in" suffix are preprocessed via CPP(1).  This can be useful
       to  decompose  Containerfiles  into  several  reusable  parts  that  can be used via CPP's
       #include directive. Containerfiles ending in .in are restricted to no comment lines unless
       they  are  CPP  commands.   Note, a Containerfile.in file can still be used by other tools
       when manually preprocessing them via cpp -E.

       When the URL is an archive, the contents of the URL is downloaded to a temporary  location
       and extracted before execution.

       When the URL is a Containerfile, the Containerfile is downloaded to a temporary location.

       When  a Git repository is set as the URL, the repository is cloned locally and then set as
       the context.

       NOTE: podman build uses code sourced from the Buildah project to build  container  images.
       This  Buildah code creates Buildah containers for the RUN options in container storage. In
       certain situations, when the podman build crashes or users kill the podman build  process,
       these  external  containers  can  be  left  in  container storage. Use the podman ps --all
       --storage command to see these containers. External containers can  be  removed  with  the
       podman rm --storage command.

       podman  buildx  build  command is an alias of podman build.  Not all buildx build features
       are available in Podman. The buildx build option is provided for scripting compatibility.

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.

   --all-platforms
       Instead  of building for a set of platforms specified using the --platform option, inspect
       the build's base images, and build for all  of  the  platforms  for  which  they  are  all
       available.   Stages that use scratch as a starting point can not be inspected, so at least
       one non-scratch stage must be present for detection to work usefully.

   --annotation=annotation=value
       Add an image annotation (e.g.  annotation=value)  to  the  image  metadata.  Can  be  used
       multiple times.

       Note:  this  information  is  not present in Docker image formats, so it is discarded when
       writing images in Docker formats.

   --arch=arch
       Set the architecture of the image to be built, and that of the base image to be pulled, if
       the  build  uses one, to the provided value instead of using the architecture of the build
       host. Unless overridden, subsequent lookups of the same image in the local storage matches
       this  architecture,  regardless  of  the host. (Examples: arm, arm64, 386, amd64, ppc64le,
       s390x)

   --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.

   --build-arg=arg=value
       Specifies  a build argument and its value, which is interpolated in instructions read from
       the Containerfiles in the same way that environment variables are, but which are not added
       to environment variable list in the resulting image's configuration.

   --build-arg-file=path
       Specifies a file containing lines of build arguments of the form arg=value.  The suggested
       file name is argfile.conf.

       Comment lines beginning with # are ignored, along with blank lines.  All others must be of
       the arg=value format passed to --build-arg.

       If  several  arguments  are provided via the --build-arg-file and --build-arg options, the
       build arguments are merged across all of the provided files and command line arguments.

       Any file provided in a --build-arg-file option is read before the arguments  supplied  via
       the --build-arg option.

       When  a  given argument name is specified several times, the last instance is the one that
       is passed to the resulting builds. This means --build-arg values always override those  in
       a --build-arg-file.

   --build-context=name=value
       Specify  an  additional  build  context using its short name and its location.  Additional
       build contexts can be referenced in the same manner as we access different stages in  COPY
       instruction.

       Valid values are:

              • Local  directory  –  e.g.  --build-context project2=../path/to/project2/src (This
                option is not available with the remote Podman client. On  Podman  machine  setup
                (i.e macOS and Winows) path must exists on the machine VM)

              • HTTP       URL       to      a      tarball      –      e.g.      --build-context
                src=https://example.org/releases/src.tar

              • Container image – specified  with  a  container-image://  prefix,  e.g.  --build-
                context  alpine=container-image://alpine:3.15,  (also  accepts docker://, docker-
                image://)

       On the Containerfile side, reference the build context on all  commands  that  accept  the
       “from” parameter. Here’s how that might look:

       FROM [name]
       COPY --from=[name] ...
       RUN --mount=from=[name] …

       The value of [name] is matched with the following priority order:

              • Named build context defined with --build-context [name]=..

              • Stage defined with AS [name] inside Containerfile

              • Image [name], either local or in a remote registry

   --cache-from=image
       Repository  to  utilize as a potential cache source. When specified, Buildah tries to look
       for cache images in the specified repository and attempts to pull cache images instead  of
       actually  executing  the  build  steps  locally.  Buildah only attempts to pull previously
       cached images if they are considered as valid cache hits.

       Use the --cache-to option to populate a remote repository with cache content.

       Example

       # populate a cache and also consult it
       buildah build -t test --layers --cache-to registry/myrepo/cache --cache-from registry/myrepo/cache .

       Note: --cache-from option is ignored unless --layers is specified.

   --cache-to=image
       Set this flag to specify a remote repository that is used to store cache  images.  Buildah
       attempts to push newly built cache image to the remote repository.

       Note: Use the --cache-from option in order to use cache content in a remote repository.

       Example

       # populate a cache and also consult it
       buildah build -t test --layers --cache-to registry/myrepo/cache --cache-from registry/myrepo/cache .

       Note: --cache-to option is ignored unless --layers is specified.

   --cache-ttl
       Limit  the  use of cached images to only consider images with created timestamps less than
       duration ago.  For example if --cache-ttl=1h is specified, Buildah considers  intermediate
       cache  images  which  are  created  under the duration of one hour, and intermediate cache
       images outside this duration is ignored.

       Note:  Setting  --cache-ttl=0  manually  is  equivalent  to  using   --no-cache   in   the
       implementation since this means that the user dones not want to use cache at all.

   --cap-add=CAP_xxx
       When  executing  RUN  instructions,  run the command specified in the instruction with the
       specified capability added to its capability set.  Certain  capabilities  are  granted  by
       default; this option can be used to add more.

   --cap-drop=CAP_xxx
       When  executing  RUN  instructions,  run the command specified in the instruction with the
       specified capability removed from its capability set.   The  CAP_CHOWN,  CAP_DAC_OVERRIDE,
       CAP_FOWNER,   CAP_FSETID,   CAP_KILL,   CAP_NET_BIND_SERVICE,   CAP_SETFCAP,   CAP_SETGID,
       CAP_SETPCAP, and CAP_SETUID capabilities are granted by default; this option can  be  used
       to remove them.

       If  a capability is specified to both the --cap-add and --cap-drop options, it is dropped,
       regardless of the order in which the options were given.

   --cert-dir=path
       Use certificates at path (*.crt, *.cert, *.key) to  connect  to  the  registry.  (Default:
       /etc/containers/certs.d)  For  details,  see  containers-certs.d(5).   (This option is not
       available with the remote Podman  client,  including  Mac  and  Windows  (excluding  WSL2)
       machines)

   --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=how
       Sets  the  configuration  for  cgroup  namespaces  when  handling  RUN  instructions.  The
       configured value can be "" (the empty string) or "private" to indicate that a  new  cgroup
       namespace  is  created, or it can be "host" to indicate that the cgroup namespace in which
       buildah itself is being run is reused.

   --compress
       This option is added to be aligned with other containers CLIs.  Podman doesn't communicate
       with  a  daemon  or  a  remote  server.   Thus,  compressing the data before sending it is
       irrelevant to Podman. (This option  is  not  available  with  the  remote  Podman  client,
       including Mac and Windows (excluding WSL2) machines)

   --cpp-flag=flags
       Set  additional  flags  to pass to the C Preprocessor cpp(1). Containerfiles ending with a
       ".in" suffix is preprocessed via cpp(1). This option can be used to pass additional  flags
       to cpp.Note: You can also set default CPPFLAGS by setting the BUILDAH_CPPFLAGS environment
       variable (e.g., export BUILDAH_CPPFLAGS="-DDEBUG").

   --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).

       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-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:

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

       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.

   --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).

       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.

   --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.

       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.

   --creds=[username[:password]]
       The [username[:password]] to use to authenticate with the registry, if required.   If  one
       or  both  values  are  not  supplied,  a  command line prompt appears and the value can be
       entered. The password is entered without echo.

       Note that  the  specified  credentials  are  only  used  to  authenticate  against  target
       registries.   They  are  not  used  for  mirrors  or when the registry gets rewritten (see
       containers-registries.conf(5)); to authenticate against those consider using a containers-
       auth.json(5) file.

   --cw=options
       Produce  an  image  suitable  for  use  as  a  confidential  workload running in a trusted
       execution environment (TEE) using krun (i.e., crun built with the libkrun feature  enabled
       and  invoked  as  krun).  Instead of the conventional contents, the root filesystem of the
       image will contain an encrypted disk image and configuration information for krun.

       The  value  for  options  is  a  comma-separated  list  of  key=value   pairs,   supplying
       configuration  information which is needed for producing the additional data which will be
       included in the container image.

       Recognized keys are:

       attestation_url: The location of a key  broker  /  attestation  server.   If  a  value  is
       specified, the new image's workload ID, along with the passphrase used to encrypt the disk
       image, will be registered with the server, and the server's location will be stored in the
       container  image.   At  run-time,  krun  is expected to contact the server to retrieve the
       passphrase using the workload ID, which is also stored in  the  container  image.   If  no
       value is specified, a passphrase value must be specified.

       cpus:  The  number of virtual CPUs which the image expects to be run with at run-time.  If
       not specified, a default value will be supplied.

       firmware_library: The location of the libkrunfw-sev shared  library.   If  not  specified,
       buildah checks for its presence in a number of hard-coded locations.

       memory:  The  amount  of  memory  which the image expects to be run with at run-time, as a
       number of megabytes.  If not specified, a default value will be supplied.

       passphrase: The passphrase to use to encrypt the disk image which will be included in  the
       container  image.   If no value is specified, but an attestation_url value is specified, a
       randomly-generated  passphrase  will  be  used.   The   authors   recommend   setting   an
       attestation_url but not a passphrase.

       slop:  Extra  space  to  allocate for the disk image compared to the size of the container
       image's contents, expressed either as a percentage (..%) or a size value (bytes, or larger
       units if suffixes like KB or MB are present), or a sum of two or more such specifications.
       If not specified, buildah guesses that 25% more space than the contents  will  be  enough,
       but this option is provided in case its guess is wrong.

       type: The type of trusted execution environment (TEE) which the image should be marked for
       use with.  Accepted values are "SEV" (AMD  Secure  Encrypted  Virtualization  -  Encrypted
       State)  and  "SNP"  (AMD  Secure Encrypted Virtualization - Secure Nested Paging).  If not
       specified, defaults to "SNP".

       workload_id: A workload identifier which will be recorded in the container  image,  to  be
       used  at  run-time for retrieving the passphrase which was used to encrypt the disk image.
       If not specified, a semi-random value will be derived from the base image's image ID.

       This option is not supported on the remote client, including Mac  and  Windows  (excluding
       WSL2) machines.

   --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. The crun(1) runtime offers a workaround for this by adding the
       option --annotation run.oci.keep_original_groups=1.

   --disable-compression, -D
       Don't compress filesystem layers when building the image unless  it  is  required  by  the
       location  where  the  image  is being written.  This is the default setting, because image
       layers are compressed automatically when they are pushed to registries, and  images  being
       written to local storage only need to be decompressed again to be stored.  Compression can
       be forced in all cases by specifying --disable-compression=false.

   --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.

       Note:  this  option  takes  effect only during RUN instructions in the build.  It does not
       affect /etc/resolv.conf in the final image.

   --dns-option=option
       Set custom DNS options to be used during the build.

   --dns-search=domain
       Set custom DNS search domains to be used during the build.

   --env=env[=value]
       Add a value (e.g. env=value) to the built image.  Can be used multiple times.  If  neither
       = nor a value are specified, but env is set in the current environment, the value from the
       current environment is added to the image.  To remove an  environment  variable  from  the
       built image, use the --unsetenv option.

   --file, -f=Containerfile
       Specifies  a  Containerfile  which  contains instructions for building the image, either a
       local file or an http or https URL.  If more than one  Containerfile  is  specified,  FROM
       instructions are only be accepted from the last specified file.

       If  a  build context is not specified, and at least one Containerfile is a local file, the
       directory in which it resides is used as the build context.

       Specifying the option -f - causes the Containerfile contents to be read from stdin.

   --force-rm
       Always remove intermediate containers after a build, even  if  the  build  fails  (default
       true).

   --format
       Control  the  format  for  the  built image's manifest and configuration data.  Recognized
       formats include oci (OCI image-spec v1.0, the default) and docker (version 2, using schema
       format 2 for the manifest).

       Note:  You  can also override the default format by setting the BUILDAH_FORMAT environment
       variable.  export BUILDAH_FORMAT=docker

   --from
       Overrides the first FROM instruction within the Containerfile.  If there are multiple FROM
       instructions in a Containerfile, only the first is changed.

       With the remote podman client, not all container transports work as expected. For example,
       oci-archive:/x.tar references /x.tar on the remote machine instead of on the client.  When
       using  podman  remote  clients  it  is  best  to  restrict  use to containers-storage, and
       docker:// transports.

   --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)

   --help, -h
       Print usage statement

   --hooks-dir=path
       Each  *.json  file  in  the  path configures a hook for buildah build containers. For more
       details on the syntax of the JSON files and  the  semantics  of  hook  injection.  Buildah
       currently  support  both  the  1.0.0  and 0.1.0 hook schemas, although the 0.1.0 schema is
       deprecated.

       This option may be set multiple times; paths from later options have higher precedence.

       For the annotation conditions, buildah uses any  annotations  set  in  the  generated  OCI
       configuration.

       For the bind-mount conditions, only mounts explicitly requested by the caller via --volume
       are considered. Bind mounts that buildah  inserts  by  default  (e.g.  /dev/shm)  are  not
       considered.

       If   --hooks-dir   is   unset   for   root   callers,   Buildah   currently   defaults  to
       /usr/share/containers/oci/hooks.d and /etc/containers/oci/hooks.d in order  of  increasing
       precedence. Using these defaults is deprecated. Migrate to explicitly setting --hooks-dir.

   --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.

   --identity-label
       Adds default identity label io.buildah.version if set. (default true).

   --ignorefile
       Path to an alternative .containerignore file.

   --iidfile=ImageIDfile
       Write the built image's ID to the file.  When --platform  is  specified  more  than  once,
       attempting to use this option triggers an error.

   --ipc=how
       Sets  the configuration for IPC namespaces when handling RUN instructions.  The configured
       value can be "" (the empty string) or "container" to indicate that a new IPC namespace  is
       created,  or it can be "host" to indicate that the IPC namespace in which podman itself is
       being run is reused, or it can be the path to an IPC namespace which is already in use  by
       another process.

   --isolation=type
       Controls what type of isolation is used for running processes as part of RUN instructions.
       Recognized types  include  oci  (OCI-compatible  runtime,  the  default),  rootless  (OCI-
       compatible  runtime  invoked  using  a  modified  configuration  and its --rootless option
       enabled, with --no-new-keyring --no-pivot added to its create invocation, with network and
       UTS  namespaces  disabled,  and  IPC,  PID,  and  user namespaces enabled; the default for
       unprivileged users), and chroot (an internal wrapper that leans more toward chroot(1) than
       container technology).

       Note:  You  can  also override the default isolation type by setting the BUILDAH_ISOLATION
       environment variable.  export BUILDAH_ISOLATION=oci

   --jobs=number
       Run up to N concurrent stages in parallel.  If the number of jobs is greater than 1, stdin
       is  read  from /dev/null.  If 0 is specified, then there is no limit in the number of jobs
       that run in parallel.

   --label=label
       Add an image label (e.g. label=value) to the image metadata. Can be used multiple times.

       Users can set a special LABEL io.containers.capabilities=CAP1,CAP2,CAP3 in a Containerfile
       that  specifies the list of Linux capabilities required for the container to run properly.
       This label specified in a container image tells Podman to  run  the  container  with  just
       these capabilities. Podman launches the container with just the specified capabilities, as
       long as this list of capabilities is a subset of the default list.

       If the specified capabilities are not in the default set, Podman prints an  error  message
       and runs the container with the default capabilities.

   --layer-label=label[=value]
       Add  an intermediate image label (e.g. label=value) to the intermediate image metadata. It
       can be used multiple times.

       If label is named, but neither = nor a value is provided, then the  label  is  set  to  an
       empty value.

   --layers
       Cache intermediate images during the build process (Default is true).

       Note:  You  can  also  override  the default value of layers by setting the BUILDAH_LAYERS
       environment variable. export BUILDAH_LAYERS=true

   --logfile=filename
       Log output which is sent to standard output and  standard  error  to  the  specified  file
       instead  of  to  standard  output and standard error.  This option is not supported on the
       remote client, including Mac and Windows (excluding WSL2) machines.

   --logsplit=bool-value
       If --logfile and --platform are specified, the --logsplit option allows end-users to split
       the   log   file  for  each  platform  into  different  files  in  the  following  format:
       ${logfile}_${platform-os}_${platform-arch}.  This option is not supported  on  the  remote
       client, including Mac and Windows (excluding WSL2) machines.

   --manifest=manifest
       Name  of  the  manifest  list to which the image is added. Creates the manifest list if it
       does not exist. This option is useful for building multi architecture images.

   --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-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.

   --network=mode, --net
       Sets the configuration for network namespaces when handling RUN instructions.

       Valid mode values are:

              • none: no networking.

              • host:  use the Podman host network stack. 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 (default)

              • <network name|ID>: Join the network with the given name or ID, e.g. use --network
                mynet to join the network with the name mynet. Only supported for rootful users.

              • 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.

              • 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 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

   --no-cache
       Do not use existing cached images for the container build. Build from the start with a new
       set of cached layers.

   --no-hostname
       Do not create the /etc/hostname file in the container for RUN instructions.

       By default, Buildah manages the /etc/hostname file, adding the container's  own  hostname.
       When  the  --no-hostname  option  is  set,  the  image's  /etc/hostname  will be preserved
       unmodified if it exists.

   --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.

   --omit-history
       Omit build history information in the built image. (default false).

       This option is useful for the cases where end users explicitly want to set  --omit-history
       to  omit  the  optional  History from built images or when working with images built using
       build tools that do not include History information in their images.

   --os=string
       Set the OS of the image to be built, and that of the base image to be pulled, if the build
       uses  one,  instead  of  using  the  current  operating  system  of the build host. Unless
       overridden, subsequent lookups of the same image in the local  storage  matches  this  OS,
       regardless of the host.

   --os-feature=feature
       Set  the  name  of  a  required operating system feature for the image which is built.  By
       default, if the image is not based on scratch, the base image's required OS  feature  list
       is  kept,  if the base image specified any.  This option is typically only meaningful when
       the image's OS is Windows.

       If feature has a trailing -, then the feature is removed from the set of required features
       which is listed in the image.

   --os-version=version
       Set the exact required operating system version for the image which is built.  By default,
       if the image is not based on scratch, the base image's required OS version is kept, if the
       base image specified one.  This option is typically only meaningful when the image's OS is
       Windows, and is typically set in Windows base images, so  using  this  option  is  usually
       unnecessary.

   --output, -o=output-opts
       Output destination (format: type=local,dest=path)

       The  --output (or -o) option extends the default behavior of building a container image by
       allowing users to export the contents of the image as files on the local filesystem, which
       can  be  useful  for  generating local binaries, code generation, etc. (This option is not
       available with the remote Podman  client,  including  Mac  and  Windows  (excluding  WSL2)
       machines)

       The  value  for  --output  is  a comma-separated sequence of key=value pairs, defining the
       output type and options.

       Supported keys are: - dest: Destination path for exported output. Valid value is  absolute
       or  relative  path, - means the standard output.  - type: Defines the type of output to be
       used. Valid values is documented below.

       Valid type values are: - local: write the resulting build files  to  a  directory  on  the
       client-side.  - tar: write the resulting files as a single tarball (.tar).

       If  no type is specified, the value defaults to local.  Alternatively, instead of a comma-
       separated sequence, the value of --output can be just a destination (in the  dest  format)
       (e.g. --output some-path, --output -) where --output some-path is treated as if type=local
       and --output - is treated as if type=tar.

   --pid=pid
       Sets the configuration for PID namespaces when handling RUN instructions.  The  configured
       value  can be "" (the empty string) or "container" to indicate that a new PID namespace is
       created, or it can be "host" to indicate that the PID namespace in which podman itself  is
       being  run  is reused, or it can be the path to a PID namespace which is already in use by
       another process.

   --platform=os/arch[/variant][,...]
       Set the os/arch of the built image (and its base image, when using one)  to  the  provided
       value  instead  of  using  the  current operating system and architecture of the host (for
       example linux/arm).  Unless overridden, subsequent lookups of the same image in the  local
       storage matches this platform, regardless of the host.

       If  --platform  is  set,  then  the  values  of the --arch, --os, and --variant options is
       overridden.

       The --platform option can be specified more than once, or given a comma-separated list  of
       values  as  its argument.  When more than one platform is specified, the --manifest option
       is used instead of the --tag option.

       Os/arch pairs are those used by the Go Programming Language.  In several  cases  the  arch
       value  for  a  platform differs from one produced by other tools such as the arch command.
       Valid OS and architecture name combinations are listed as values for $GOOS and $GOARCH  at
       https://golang.org/doc/install/source#environment,  and  can  also  be found by running go
       tool dist list.

       While podman build is happy to use base images and build  images  for  any  platform  that
       exists,  RUN  instructions  are  able to succeed without the help of emulation provided by
       packages like qemu-user-static.

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

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

              • missing: Only pull the image when it does  not  exist  in  the  local  containers
                storage.  Throw an error if no image is found and the pull fails.

              • never,  false:  Never  pull  the  image but use the one from the local containers
                storage.  Throw an error when 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.

       Pull image policy. The default is missing.

   --quiet, -q
       Suppress  output  messages  which  indicate  which  instruction is being processed, and of
       progress when pulling images from a registry, and when writing the output image.

   --retry=attempts
       Number of times to retry in case of failure when performing pull of images from  registry.
       Default is 3.

   --retry-delay=duration
       Duration of delay between retry attempts in case of failure when performing pull of images
       from registry. Default is 2s.

   --rm
       Remove intermediate containers after a successful build (default true).

   --runtime=path
       The path to an alternate OCI-compatible runtime, which is used to run  commands  specified
       by the RUN instruction.

       Note: You can also override the default runtime by setting the BUILDAH_RUNTIME environment
       variable.  export BUILDAH_RUNTIME=/usr/local/bin/runc

   --runtime-flag=flag
       Adds global flags for the container rutime. To list the supported  flags,  please  consult
       the manpages of the selected container runtime.

       Note:  Do  not pass the leading -- to the flag. To pass the runc flag --log-format json to
       buildah build, the option given is --runtime-flag log-format=json.

   --secret=id=id,src=path
       Pass secret information used in the Containerfile for building images in a safe  way  that
       are  not  stored in the final image, or be seen in other stages.  The secret is mounted in
       the container at the default location of /run/secrets/id.

       To later  use  the  secret,  use  the  --mount  option  in  a  RUN  instruction  within  a
       Containerfile:

       RUN --mount=type=secret,id=mysecret cat /run/secrets/mysecret

   --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

              • no-new-privileges   : Not supported

              • 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

   --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.

   --sign-by=fingerprint
       Sign the image using a GPG key  with  the  specified  FINGERPRINT.  (This  option  is  not
       available  with  the  remote  Podman  client,  including  Mac and Windows (excluding WSL2)
       machines,)

   --skip-unused-stages
       Skip stages in multi-stage builds which don't affect the target stage. (Default: true).

   --squash
       Squash all of the image's new layers into a single new layer; any preexisting  layers  are
       not squashed.

   --squash-all
       Squash  all of the new image's layers (including those inherited from a base image) into a
       single new layer.

   --ssh=default | id[=socket>
       SSH agent socket or keys to expose to the build.  The socket path can be left empty to use
       the value of default=$SSH_AUTH_SOCK

       To  later  use  the  ssh  agent,  use  the  --mount  option  in a RUN instruction within a
       Containerfile:

       RUN --mount=type=ssh,id=id mycmd

   --stdin
       Pass stdin into the RUN containers. Sometime commands being  RUN  within  a  Containerfile
       want  to  request information from the user. For example apt asking for a confirmation for
       install.  Use --stdin to be able to interact from the terminal during the build.

   --tag, -t=imageName
       Specifies the name which is assigned to the resulting image if the build process completes
       successfully.   If imageName does not include a registry name, the registry name localhost
       is prepended to the image name.

   --target=stageName
       Set the target build stage to build.  When building a Containerfile  with  multiple  build
       stages,  --target  can be used to specify an intermediate build stage by name as the final
       stage for the resulting image. Commands after the target stage is skipped.

   --timestamp=seconds
       Set the create timestamp  to  seconds  since  epoch  to  allow  for  deterministic  builds
       (defaults  to current time). By default, the created timestamp is changed and written into
       the image manifest with every commit, causing the image's sha256 hash to be different even
       if  the  sources  are  exactly  the  same otherwise.  When --timestamp is set, the created
       timestamp is always set to the time specified and  therefore  not  changed,  allowing  the
       image's  sha256 hash to remain the same. All files committed to the layers of the image is
       created with the timestamp.

       If the only instruction in a Containerfile is FROM, this flag has no effect.

   --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)

   --ulimit=type=soft-limit[:hard-limit]
       Specifies resource limits to apply to processes launched when processing RUN instructions.
       This option can be specified multiple times.  Recognized resource types include:
         "core": maximum core dump size (ulimit -c)
         "cpu": maximum CPU time (ulimit -t)
         "data": maximum size of a process's data segment (ulimit -d)
         "fsize": maximum size of new files (ulimit -f)
         "locks": maximum number of file locks (ulimit -x)
         "memlock": maximum amount of locked memory (ulimit -l)
         "msgqueue": maximum amount of data in message queues (ulimit -q)
         "nice": niceness adjustment (nice -n, ulimit -e)
         "nofile": maximum number of open files (ulimit -n)
         "nproc": maximum number of processes (ulimit -u)
         "rss": maximum size of a process's (ulimit -m)
         "rtprio": maximum real-time scheduling priority (ulimit -r)
         "rttime": maximum amount of real-time execution between blocking syscalls
         "sigpending": maximum number of pending signals (ulimit -i)
         "stack": maximum stack size (ulimit -s)

   --unsetenv=env
       Unset environment variables from the final image.

   --unsetlabel=label
       Unset the image label, causing the label not to be inherited from the base image.

   --userns=how
       Sets the configuration for user namespaces when handling RUN instructions.  The configured
       value can be "" (the empty string) or "container" to indicate that a new user namespace is
       created, it can be "host" to indicate that the user namespace in which  podman  itself  is
       being  run is reused, or it can be the path to a user namespace which is already in use by
       another process.

   --userns-gid-map=mapping
       Directly specifies a GID mapping to be used to set ownership, at the filesystem level,  on
       the working container's contents.  Commands run when handling RUN instructions defaults to
       being run in their own user namespaces, configured using the UID and GID maps.

       Entries in this map take the form of one or more triples of a starting in-container GID, a
       corresponding  starting  host-level  GID,  and the number of consecutive IDs which the map
       entry represents.

       This   option   overrides   the   remap-gids   setting   in   the   options   section   of
       /etc/containers/storage.conf.

       If  this  option  is  not  specified,  but  a global --userns-gid-map setting is supplied,
       settings from the global option is used.

       If  none  of  --userns-uid-map-user,  --userns-gid-map-group,  or   --userns-gid-map   are
       specified,  but  --userns-uid-map is specified, the GID map is set to use the same numeric
       values as the UID map.

   --userns-gid-map-group=group
       Specifies that a GID mapping to be used to set ownership, at the filesystem level, on  the
       working  container's  contents,  can  be  found  in  entries in the /etc/subgid file which
       correspond to the specified group.  Commands run when handling RUN  instructions  defaults
       to  being  run  in  their  own user namespaces, configured using the UID and GID maps.  If
       --userns-uid-map-user is specified, but --userns-gid-map-group is  not  specified,  podman
       assumes  that  the specified user name is also a suitable group name to use as the default
       setting for this option.

       NOTE: When this option is specified  by  a  rootless  user,  the  specified  mappings  are
       relative  to  the  rootless user namespace in the container, rather than being relative to
       the host as it is when run rootful.

   --userns-uid-map=mapping
       Directly specifies a UID mapping to be used to set ownership, at the filesystem level,  on
       the  working container's contents.  Commands run when handling RUN instructions default to
       being run in their own user namespaces, configured using the UID and GID maps.

       Entries in this map take the form of one or more triples of a starting in-container UID, a
       corresponding  starting  host-level  UID,  and the number of consecutive IDs which the map
       entry represents.

       This   option   overrides   the   remap-uids   setting   in   the   options   section   of
       /etc/containers/storage.conf.

       If  this  option  is  not  specified,  but  a global --userns-uid-map setting is supplied,
       settings from the global option is used.

       If  none  of  --userns-uid-map-user,  --userns-gid-map-group,  or   --userns-uid-map   are
       specified,  but  --userns-gid-map is specified, the UID map is set to use the same numeric
       values as the GID map.

   --userns-uid-map-user=user
       Specifies that a UID mapping to be used to set ownership, at the filesystem level, on  the
       working  container's  contents,  can  be  found  in  entries in the /etc/subuid file which
       correspond to the specified user.  Commands run when handling RUN instructions defaults to
       being  run  in  their  own  user  namespaces,  configured  using the UID and GID maps.  If
       --userns-gid-map-group is specified, but --userns-uid-map-user is  not  specified,  podman
       assumes  that  the specified group name is also a suitable user name to use as the default
       setting for this option.

       NOTE: When this option is specified  by  a  rootless  user,  the  specified  mappings  are
       relative  to  the  rootless user namespace in the container, rather than being relative to
       the host as it is when run rootful.

   --uts=how
       Sets the configuration for UTS namespaces when handling RUN instructions.  The  configured
       value  can be "" (the empty string) or "container" to indicate that a new UTS namespace to
       be created, or it can be "host" to indicate that the UTS namespace in which podman  itself
       is  being  run is reused, or it can be the path to a UTS namespace which is already in use
       by another process.

   --variant=variant
       Set the architecture variant of the image to be built, and that of the base  image  to  be
       pulled,  if  the  build  uses one, to the provided value instead of using the architecture
       variant of the build host.

   --volume, -v=[HOST-DIR:CONTAINER-DIR[:OPTIONS]]
       Mount a host directory into containers when executing RUN instructions during the build.

       The OPTIONS are a comma-separated list and can be: [1] ⟨#Footnote1⟩

              • [rw|ro]

              • [z|Z|O]

              • [U]

              • [[r]shared|[r]slave|[r]private]

       The CONTAINER-DIR must be an absolute path such as /src/docs.  The  HOST-DIR  must  be  an
       absolute  path  as  well.  Podman  bind-mounts  the  HOST-DIR  to  the specified path when
       processing RUN instructions.

       You can specify multiple  -v options to mount one or more mounts.

       You can add the :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. When running using user namespaces, the UID and  GID  inside  the  namespace  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 namespace, to change recursively the owner and group of the source volume.

       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 one of these 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  the  host  machine to fail.  For these types of containers,
       disabling SELinux separation is  recommended.   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 the build containers, they need to disable  SELinux
       separation.

          $ podman build --security-opt label=disable -v $HOME:/home/user .

       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 RUN command containers are allowed to modify contents  within
       the  mountpoint  and  are  stored  in  the  container storage in a separate directory.  In
       Overlay FS terms the source directory is the lower, and the container storage directory is
       the  upper.  Modifications  to the mount point are destroyed when the RUN command finishes
       executing, similar to a tmpfs mount point.

       Any subsequent execution of RUN commands sees the original source directory  content,  any
       changes from previous RUN commands no longer exists.

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

       Note:

        - Overlay mounts are not currently supported in rootless mode.
        - The `O` flag is not allowed to be specified with the `Z` or `z` flags.

       Content mounted into the container is labeled with the private label.
              On SELinux systems, labels in the source directory needs  to  be  readable  by  the
       container  label.  If not, SELinux container separation must be disabled for the container
       to work.
            - Modification of the directory volume mounted into the  container  with  an  overlay
       mount  can  cause  unexpected  failures.  Do  not modify the directory until the container
       finishes running.

       By default bind mounted volumes are private. That means any mounts done inside  containers
       are  not be visible on the host and vice versa. This behavior can be changed by specifying
       a volume mount propagation property.

       When the mount propagation policy is set  to  shared,  any  mounts  completed  inside  the
       container  on  that  volume  is  visible  to  both  the host and container. When the mount
       propagation policy is set to slave, one way mount propagation is enabled  and  any  mounts
       completed  on the host for that volume is visible only inside of the container. To control
       the mount propagation property of volume use  the  :[r]shared,  :[r]slave  or  :[r]private
       propagation  flag.  For  mount  propagation to work on the source mount point (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
       has to be either shared or slave. [1] ⟨#Footnote1⟩

       Use  df  <source-dir>  to  determine  the  source  mount   and   then   use   findmnt   -o
       TARGET,PROPAGATION <source-mount-dir> to determine propagation properties of source mount,
       if findmnt utility is not available, the source mount point can be determined  by  looking
       at  the  mount  entry  in  /proc/self/mountinfo.  Look  at  optional fields and see if any
       propagation properties are specified.  shared:X means the mount is shared, master:X  means
       the  mount  is  slave  and  if  nothing  is  there  that  means  the mount is private. [1]
       ⟨#Footnote1⟩

       To change propagation properties of a mount point use the mount command. For  example,  to
       bind  mount  the  source directory /foo do mount --bind /foo /foo and mount --make-private
       --make-shared /foo. This converts  /foo  into  a  shared  mount  point.   The  propagation
       properties  of  the  source mount can be changed directly. For instance if / is the source
       mount for /foo, then use mount --make-shared / to convert / into a shared mount.

EXAMPLES

   Build an image using local Containerfiles
       $ podman build .

       $ podman build -f Containerfile.simple .

       $ cat $HOME/Containerfile | podman build -f - .

       $ podman build -f Containerfile.simple -f Containerfile.notsosimple .

       $ podman build -f Containerfile.in $HOME

       $ podman build -t imageName .

       $ podman build --tls-verify=true -t imageName -f Containerfile.simple .

       $ podman build --tls-verify=false -t imageName .

       $ podman build --runtime-flag log-format=json .

       $ podman build --runtime-flag debug .

       $ podman build --authfile /tmp/auths/myauths.json --cert-dir $HOME/auth --tls-verify=true --creds=username:password -t imageName -f Containerfile.simple .

       $ podman build --memory 40m --cpu-period 10000 --cpu-quota 50000 --ulimit nofile=1024:1028 -t imageName .

       $ podman build --security-opt label=level:s0:c100,c200 --cgroup-parent /path/to/cgroup/parent -t imageName .

       $ podman build --volume /home/test:/myvol:ro,Z -t imageName .

       $ podman build -v /var/lib/yum:/var/lib/yum:O -t imageName .

       $ podman build --layers -t imageName .

       $ podman build --no-cache -t imageName .

       $ podman build --layers --force-rm -t imageName .

       $ podman build --no-cache --rm=false -t imageName .

       $ podman build --network mynet .

   Building a multi-architecture image using the --manifest option (requires emulation software)
       $ podman build --arch arm --manifest myimage /tmp/mysrc

       $ podman build --arch amd64 --manifest myimage /tmp/mysrc

       $ podman build --arch s390x --manifest myimage /tmp/mysrc

       $ podman build --platform linux/s390x,linux/ppc64le,linux/amd64 --manifest myimage /tmp/mysrc

       $ podman build --platform linux/arm64 --platform linux/amd64 --manifest myimage /tmp/mysrc

   Building an image using a URL, Git repo, or archive
       The build context directory  can  be  specified  as  a  URL  to  a  Containerfile,  a  Git
       repository,  or  URL  to  an archive. If the URL is a Containerfile, it is downloaded to a
       temporary location and used as the context. When a Git repository is set as the  URL,  the
       repository is cloned locally to a temporary location and then used as the context. Lastly,
       if the URL is an archive, it is downloaded to a temporary location  and  extracted  before
       being used as the context.

   Building an image using a URL to a Containerfile
       Podman  downloads  the  Containerfile to a temporary location and then use it as the build
       context.

       $ podman build https://10.10.10.1/podman/Containerfile

   Building an image using a Git repository
       Podman clones the specified GitHub repository to a temporary location and use  it  as  the
       context.  The Containerfile at the root of the repository is used and it only works if the
       GitHub repository is a dedicated repository.

       $ podman build -t hello  https://github.com/containers/PodmanHello.git
       $ podman run hello

       Note: Github does not support using git:// for performing clone operation  due  to  recent
       changes in their security guidance (https://github.blog/2021-09-01-improving-git-protocol-
       security-github/). Use an https:// URL if the source repository is hosted on Github.

   Building an image using a URL to an archive
       Podman fetches the archive file, decompress it, and use its contents as the build context.
       The  Containerfile  at the root of the archive and the rest of the archive are used as the
       context of the build. Passing the -f PATH/Containerfile option as well tells the system to
       look for that file inside the contents of the archive.

       $ podman build -f dev/Containerfile https://10.10.10.1/podman/context.tar.gz

       Note:  supported  compression  formats  are  'xz',  'bzip2',  'gzip'  and  'identity'  (no
       compression).

Files

   .containerignore/.dockerignore
       If the file .containerignore or .dockerignore exists  in  the  context  directory,  podman
       build  reads  its  contents.  Use  the --ignorefile option to override the Podman uses the
       content to exclude files and directories from the context directory, when  executing  COPY
       and ADD directives in the Containerfile/Dockerfile

       The  .containerignore  and  .dockerignore  files  use  the same syntax; if both are in the
       context directory, podman build only uses .containerignore.

       Users can specify a series of Unix shell globs in  a  .containerignore  file  to  identify
       files/directories to exclude.

       Podman  supports  a  special  wildcard  string  ** which matches any number of directories
       (including zero). For example, */.go excludes all files that end with .go that  are  found
       in all directories.

       Example .containerignore file:

       # exclude this content for image
       */*.c
       **/output*
       src

       */*.c  Excludes  files  and  directories  whose  names  ends  with  .c  in  any  top level
       subdirectory. For example, the source file include/rootless.c.

       **/output* Excludes files and directories starting with output from any directory.

       src Excludes files named src and the directory src as well as any content in it.

       Lines starting with ! (exclamation mark) can be used to make exceptions to exclusions. The
       following is an example .containerignore file that uses this mechanism:

       *.doc
       !Help.doc

       Exclude all doc files except Help.doc from the image.

       This  functionality  is  compatible  with the handling of .containerignore files described
       here:

       https://github.com/containers/common/blob/main/docs/containerignore.5.md

       registries.conf (/etc/containers/registries.conf)

       registries.conf is the configuration file which specifies which  container  registries  is
       consulted when completing image names which do not include a registry or domain portion.

Troubleshooting

   lastlog sparse file
       Using a useradd command within a Containerfile with a large UID/GID creates a large sparse
       file /var/log/lastlog.  This can cause the build to hang forever.  Go  language  does  not
       support  sparse  files  correctly,  which can lead to some huge files being created in the
       container image.

       When using the useradd command within the build  script,  pass  the  --no-log-init  or  -l
       option  to  the  useradd  command.  This option tells useradd to stop creating the lastlog
       file.

SEE ALSO

       podman(1),  buildah(1),  containers-certs.d(5),  containers-registries.conf(5),   crun(1),
       runc(8), useradd(8), podman-ps(1), podman-rm(1), Containerfile(5), containerignore(5)

HISTORY

       Aug 2020, Additional options and .containerignore added by Dan Walsh <dwalsh@redhat.com>

       May 2018, Minor revisions added by Joe Doss <joe@solidadmin.com>

       December 2017, Originally compiled by Tom Sweeney <tsweeney@redhat.com>

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-build(1)