podman/transfer.md

PODMAN Usage Transfer

This document outlines useful information for ops and dev transfer as it relates to infrastructure that utilizes PODMAN.

Operational Transfer

Abstract

The crio daemon is intended to provide the CRI socket needed for Kubernetes to use for automating deployment, scaling, and management of containerized applications (See the document for configuring kubernetes to use PODMAN for more information on that). Therefore the crioctl command line is a client that interfaces to the same grpc socket as the kubernetes daemon would, for talking to the crio daemon. In many ways crioctl is only as feature rich as the Kubernetes CRI requires. There are additional tools e.g. podman and buildah that provide a feature rich set of commands for all operational needs in a Kubernetes environment.

System Tools

Many traditional tools will still be useful, such as pstree, nsenter and lsns. As well as some systemd helpers like systemd-cgls and systemd-cgtop are still just as applicable.

Equivalents

For many troubleshooting and information collection steps, there may be an existing pattern. Following provides equivalent with PODMAN tools for gathering information or jumping into containers, for operational use.

Existing Step	PODMAN (and friends)
docker run	podman run
docker exec	podman exec
docker info	podman info
docker inspect	podman inspect
docker logs	podman logs
docker ps	podman ps
docker stats	podman stats

Development Transfer

There are other equivalents for these tools

Existing Step	PODMAN (and friends)
docker attach	podman exec
docker build	podman build
docker commit	podman commit
docker cp	podman mount ****
docker create	podman create
docker diff	podman diff
docker export	podman export
docker history	podman history
docker images	podman images
docker import	podman import
docker kill	podman kill
docker load	podman load
docker login	podman login
docker logout	podman logout
docker pause	podman pause
docker ps	podman ps
docker pull	podman pull
docker push	podman push
docker rm	podman rm
docker rmi	podman rmi
docker run	podman run
docker save	podman save
docker start	podman start
docker stop	podman stop
docker tag	podman tag
docker top	podman top
docker unpause	podman unpause
docker version	podman version
docker wait	podman wait

**** Use mount to take advantage of the entire linux tool chain rather then just cp. Read here for more information.

Missing commands in podman

Those Docker commands currently do not have equivalents in podman:

Missing command	Description
docker container
docker events
docker image
docker network
docker node
docker plugin	podman does not support plugins. We recommend you use alternative OCI Runtimes or OCI Runtime Hooks to alter behaviour of podman.
docker port
docker rename	podman does not support rename, you need to use podman rm and podman create to rename a container.
docker restart	podman does not support restart. We recommend that you put your podman containers into a systemd unit file and use it for restarting applications.
docker search
docker secret
docker service
docker stack
docker swarm	podman does not support swarm. We support Kubernetes for orchestration using CRI-O.
docker system
docker volume	podman does not support volumes. Volumes should be built on the host operating system and then volume mounted into the containers.

Missing commands in Docker

The following podman commands do not have a Docker equivalent:

• podman mount
• podman umount