Provided by: podman_4.3.1+ds1-8ubuntu1_amd64 
NAME
podman-container-checkpoint - Checkpoints one or more running containers
SYNOPSIS
podman container checkpoint [options] container [container ...]
DESCRIPTION
podman container checkpoint checkpoints all the processes in one or more containers. A
container can be restored from a checkpoint with podman-container-restore. The container
IDs or names are used as input.
IMPORTANT: If the container is using systemd as entrypoint checkpointing the container
might not be possible.
OPTIONS
--all, -a
Checkpoint all running containers.
The default is false.
IMPORTANT: This OPTION does not need a container name or ID as input argument.
--compress, -c=zstd | none | gzip
Specify the compression algorithm used for the checkpoint archive created with the
--export, -e OPTION. Possible algorithms are zstd, none and gzip.
One possible reason to use none is to enable faster creation of checkpoint archives. Not
compressing the checkpoint archive can result in faster checkpoint archive creation.
The default is zstd.
--create-image=image
Create a checkpoint image from a running container. This is a standard OCI image created
in the local image store. It consists of a single layer that contains all of the
checkpoint files. The content of this image layer is in the same format as a checkpoint
created with --export. A checkpoint image can be pushed to a standard container registry
and pulled on a different system to enable container migration. In addition, the image can
be exported with podman image save and inspected with podman inspect. Inspecting a
checkpoint image would display additional information, stored as annotations, about the
host environment used to do the checkpoint:
• io.podman.annotations.checkpoint.name: Human-readable name of the original
container.
• io.podman.annotations.checkpoint.rawImageName: Unprocessed name of the image used
to create the original container (as specified by the user).
• io.podman.annotations.checkpoint.rootfsImageID: ID of the image used to create
the original container.
• io.podman.annotations.checkpoint.rootfsImageName: Image name used to create the
original container.
• io.podman.annotations.checkpoint.podman.version: Version of Podman used to create
the checkpoint.
• io.podman.annotations.checkpoint.criu.version: Version of CRIU used to create the
checkpoint.
• io.podman.annotations.checkpoint.runtime.name: Container runtime (e.g., runc,
crun) used to create the checkpoint.
• io.podman.annotations.checkpoint.runtime.version: Version of the container
runtime used to create the checkpoint.
• io.podman.annotations.checkpoint.conmon.version: Version of conmon used with the
original container.
• io.podman.annotations.checkpoint.host.arch: CPU architecture of the host on which
the checkpoint was created.
• io.podman.annotations.checkpoint.host.kernel: Version of Linux kernel of the host
where the checkpoint was created.
• io.podman.annotations.checkpoint.cgroups.version: cgroup version used by the host
where the checkpoint was created.
• io.podman.annotations.checkpoint.distribution.version: Version of host
distribution on which the checkpoint was created.
• io.podman.annotations.checkpoint.distribution.name: Name of host distribution on
which the checkpoint was created.
--export, -e=archive
Export the checkpoint to a tar.gz file. The exported checkpoint can be used to import the
container on another system and thus enabling container live migration. This checkpoint
archive also includes all changes to the container's root file-system, if not explicitly
disabled using --ignore-rootfs.
--file-locks
Checkpoint a container with file locks. If an application running in the container is
using file locks, this OPTION is required during checkpoint and restore. Otherwise
checkpointing containers with file locks is expected to fail. If file locks are not used,
this option is ignored.
The default is false.
--ignore-rootfs
If a checkpoint is exported to a tar.gz file it is possible with the help of --ignore-
rootfs to explicitly disable including changes to the root file-system into the checkpoint
archive file.
The default is false.
IMPORTANT: This OPTION only works in combination with --export, -e.
--ignore-volumes
This OPTION must be used in combination with the --export, -e OPTION. When this OPTION is
specified, the content of volumes associated with the container will not be included into
the checkpoint tar.gz file.
The default is false.
--keep, -k
Keep all temporary log and statistics files created by CRIU during checkpointing. These
files are not deleted if checkpointing fails for further debugging. If checkpointing
succeeds these files are theoretically not needed, but if these files are needed Podman
can keep the files for further analysis.
The default is false.
--latest, -l
Instead of providing the container ID or name, use the last created container. If other
methods than Podman are used to run containers such as CRI-O, the last started container
could be from either of those methods.
The default is false.
IMPORTANT: This OPTION is not available with the remote Podman client, including Mac and
Windows (excluding WSL2) machines. This OPTION does not need a container name or ID as
input argument.
--leave-running, -R
Leave the container running after checkpointing instead of stopping it.
The default is false.
--pre-checkpoint, -P
Dump the container's memory information only, leaving the container running. Later
operations will supersede prior dumps. It only works on runc 1.0-rc3 or higher.
The default is false.
The functionality to only checkpoint the memory of the container and in a second
checkpoint only write out the memory pages which have changed since the first checkpoint
relies on the Linux kernel's soft-dirty bit, which is not available on all systems as it
depends on the system architecture and the configuration of the Linux kernel. Podman will
verify if the current system supports this functionality and return an error if the
current system does not support it.
--print-stats
Print out statistics about checkpointing the container(s). The output is rendered in a
JSON array and contains information about how much time different checkpoint operations
required. Many of the checkpoint statistics are created by CRIU and just passed through to
Podman. The following information is provided in the JSON array:
• podman_checkpoint_duration: Overall time (in microseconds) needed to create all
checkpoints.
• runtime_checkpoint_duration: Time (in microseconds) the container runtime needed
to create the checkpoint.
• freezing_time: Time (in microseconds) CRIU needed to pause (freeze) all processes
in the container (measured by CRIU).
• frozen_time: Time (in microseconds) all processes in the container were paused
(measured by CRIU).
• memdump_time: Time (in microseconds) needed to extract all required memory pages
from all container processes (measured by CRIU).
• memwrite_time: Time (in microseconds) needed to write all required memory pages
to the corresponding checkpoint image files (measured by CRIU).
• pages_scanned: Number of memory pages scanned to determine if they need to be
checkpointed (measured by CRIU).
• pages_written: Number of memory pages actually written to the checkpoint image
files (measured by CRIU).
The default is false.
--tcp-established
Checkpoint a container with established TCP connections. If the checkpoint image contains
established TCP connections, this OPTION is required during restore. Defaults to not
checkpointing containers with established TCP connections.
The default is false.
--with-previous
Check out the container with previous criu image files in pre-dump. It only works on runc
1.0-rc3 or higher.
The default is false.
IMPORTANT: This OPTION is not available with --pre-checkpoint.
This option requires that the option --pre-checkpoint has been used before on the same
container. Without an existing pre-checkpoint, this option will fail.
Also see --pre-checkpoint for additional information about --pre-checkpoint availability
on different systems.
EXAMPLES
Make a checkpoint for the container "mywebserver".
# podman container checkpoint mywebserver
Create a checkpoint image for the container "mywebserver".
# podman container checkpoint --create-image mywebserver-checkpoint-1 mywebserver
Dumps the container's memory information of the latest container into an archive.
# podman container checkpoint -P -e pre-checkpoint.tar.gz -l
Keep the container's memory information from an older dump and add the new container's
memory information.
# podman container checkpoint --with-previous -e checkpoint.tar.gz -l
Dump the container's memory information of the latest container into an archive with the
specified compress method.
# podman container checkpoint -l --compress=none --export=dump.tar
# podman container checkpoint -l --compress=gzip --export=dump.tar.gz
SEE ALSO
podman(1), podman-container-restore(1), criu(8)
HISTORY
September 2018, Originally compiled by Adrian Reber areber@redhat.com
⟨mailto:areber@redhat.com⟩
podman-container-checkpoint(1)