From 756ecd5400c7a8806890753d4f9fbb2b39eba192 Mon Sep 17 00:00:00 2001 From: Radostin Stoyanov Date: Tue, 12 Apr 2022 18:46:32 +0100 Subject: Add support for checkpoint image This is an enhancement proposal for the checkpoint / restore feature of Podman that enables container migration across multiple systems with standard image distribution infrastructure. A new option `--create-image ` has been added to the `podman container checkpoint` command. This option tells Podman to create a container image. This is a standard image with a single layer, tar archive, that that contains all checkpoint files. This is similar to the current approach with checkpoint `--export`/`--import`. This image can be pushed to a container registry and pulled on a different system. It can also be exported locally with `podman image save` and inspected with `podman inspect`. Inspecting the image would display additional information about the host and the versions of Podman, criu, crun/runc, kernel, etc. `podman container restore` has also been extended to support image name or ID as input. Suggested-by: Adrian Reber Signed-off-by: Radostin Stoyanov --- .../markdown/podman-container-checkpoint.1.md | 59 ++++++++++++++++++++++ 1 file changed, 59 insertions(+) (limited to 'docs/source/markdown/podman-container-checkpoint.1.md') diff --git a/docs/source/markdown/podman-container-checkpoint.1.md b/docs/source/markdown/podman-container-checkpoint.1.md index 5c07cd975..a11897081 100644 --- a/docs/source/markdown/podman-container-checkpoint.1.md +++ b/docs/source/markdown/podman-container-checkpoint.1.md @@ -28,6 +28,60 @@ 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 @@ -145,6 +199,11 @@ 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 -- cgit v1.2.3-54-g00ecf