Ubuntu Manpage: podman-container-clone - Create a copy of an existing container

Provided by: podman_5.0.3+ds1-5ubuntu1_amd64

NAME

       podman-container-clone - Create a copy of an existing container

SYNOPSIS

       podman container clone [options] container name image

DESCRIPTION

       podman  container  clone  creates  a  copy of a container, recreating the original with an
       identical configuration. This command takes three arguments: the first being the container
       ID  or name to clone, the second argument in this command can change the name of the clone
       from the default of $ORIGINAL_NAME-clone, and the third is a  new  image  to  use  in  the
       cloned container.

OPTIONS

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

This option is not supported on cgroups V1 rootless systems.

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

--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.

If none is specified, the original container's cpu period is used

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

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

This option is not supported on cgroups V1 rootless systems.

If none is specified, the original container's CPU quota are used.

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

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

This option is only supported on cgroups V1 rootful systems.

If none is specified, the original container's CPU runtime period is used.

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

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

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

This option is only supported on cgroups V1 rootful systems.

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

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

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

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

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

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

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

This option is not supported on cgroups V1 rootless systems.

If none are specified, the original container's CPU shares are used.

--cpus
Set a number of CPUs for the container that overrides the original containers CPU limits.
If none are specified, the original container's Nano CPUs are used.

This is shorthand for --cpu-period and --cpu-quota, so only --cpus or either both the
--cpu-period and --cpu-quota options can be set.

This option is not supported on cgroups V1 rootless systems.

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

This option is not supported on cgroups V1 rootless systems.

If none are specified, the original container's CPUset is used.

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

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

This option is not supported on cgroups V1 rootless systems.

If none are specified, the original container's CPU memory nodes are used.

--destroy
Remove the original container that we are cloning once used to mimic the configuration.

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

This option is not supported on cgroups V1 rootless systems.

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

This option is not supported on cgroups V1 rootless systems.

--force, -f
Force removal of the original container that we are cloning. Can only be used in
conjunction with --destroy.

--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.

If no memory limits are specified, the original container's memory limits are used.

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

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

This option is not supported on cgroups V1 rootless systems.

If unspecified, memory reservation is the same as memory limit from the container being
cloned.

--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.

If unspecified, the container being cloned is used to derive the swap value.

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

This flag is only supported on cgroups V1 rootful systems.

--name
Set a custom name for the cloned container. The default if not specified is of the syntax:
<ORIGINAL_NAME>-clone

--pod=name
Clone the container in an existing pod. It is helpful to move a container to an existing
pod. The container joins the pod shared namespaces, losing its configuration that
conflicts with the shared namespaces.

--run
When set to true, this flag runs the newly created container after the clone process has
completed, this specifies a detached running mode.

EXAMPLES

       Clone specified container into a new container:

       # podman container clone d0cf1f782e2ed67e8c0050ff92df865a039186237a4df24d7acba5b1fa8cc6e7
       6b2c73ff8a1982828c9ae2092954bcd59836a131960f7e05221af9df5939c584

       Clone specified container into a newly named container:

       # podman container clone --name=clone d0cf1f782e2ed67e8c0050ff92df865a039186237a4df24d7acba5b1fa8cc6e7
       6b2c73ff8a1982828c9ae2092954bcd59836a131960f7e05221af9df5939c584

       Replace  specified  container  with  selected  resource  constraints into a new container,
       removing original container:

       # podman container clone --destroy --cpus=5 d0cf1f782e2ed67e8c0050ff92df865a039186237a4df24d7acba5b1fa8cc6e7
       6b2c73ff8a1982828c9ae2092954bcd59836a131960f7e05221af9df5939c584

       Clone specified container giving a new name and then replacing the image of  the  original
       container with the specified image name:

       # podman container clone 2d4d4fca7219b4437e0d74fcdc272c4f031426a6eacd207372691207079551de new_name fedora
       Resolved "fedora" as an alias (/etc/containers/registries.conf.d/shortnames.conf)
       Trying to pull registry.fedoraproject.org/fedora:latest...
       Getting image source signatures
       Copying blob c6183d119aa8 done
       Copying config e417cd49a8 done
       Writing manifest to image destination
       Storing signatures
       5a9b7851013d326aa4ac4565726765901b3ecc01fcbc0f237bc7fd95588a24f9

HISTORY

       January     2022,     Originally    written    by    Charlie    Doern    cdoern@redhat.com
       ⟨mailto:cdoern@redhat.com⟩

                                                                        podman-container-clone(1)

NAME

SYNOPSIS

DESCRIPTION

OPTIONS

EXAMPLES

SEE ALSO

HISTORY