Fly To Podman: a script that will help you to migrate from Docker

MrThoughtful wrote: post #3

I never tried Podman. I guess the benefit is that it runs on demand and not as a always on demon? How does one install podman on Debian and how does one get a Debian image to run inside podman?

1) Podman is available in default debian repos. https://packages.debian.org/bookworm/podman

2) `podman run --entrypoint="" --rm -it debian:stable /bin/bash`

in most instances you can just alias docker to podman and carry on. It uses OCI formatted images just like docker and uses the same registry infrastructure that docker uses.

Re: Fly To Podman: a script that will help you to migrate from Docker

#5

Post by pzmarzly » Fri, Feb 21, 2025, 1:17 PM UTC

MrThoughtful wrote: post #3

I never tried Podman. I guess the benefit is that it runs on demand and not as a always on demon? How does one install podman on Debian and how does one get a Debian image to run inside podman?

Runs on demand, doesn't require root, can be nested, usually uses newer and simpler primitives (e.g. a few nftables rules in Podman vs iptables spaghetti in Docker). In my experience it is ~90% compatible with Docker. The author explains the practical differences in the blog post https://www.edu4rdshl.dev/posts/from-docker-to-podman-full-m...

It is usually easier to install - most distros ship relatively recent version of Podman, while Docker is split between docker.io (ancient), docker-ce (free but non in repos) and docker-ee.

Not everything is rosy, some tools expect to be talking to real Docker and don't get fooled by `ln -s docker podman`. But it is almost there.

Regarding Debian, just `sudo apt install podman && podman run -it debian` - see https://wiki.debian.org/Podman

Re: Fly To Podman: a script that will help you to migrate from Docker

#6

Post by aragilar » Fri, Feb 21, 2025, 1:37 PM UTC

natebc wrote: post #4

MrThoughtful wrote: post #3

I never tried Podman. I guess the benefit is that it runs on demand and not as a always on demon? How does one install podman on Debian and how does one get a Debian image to run inside podman?

1) Podman is available in default debian repos. https://packages.debian.org/bookworm/podman 2) `podman run --entrypoint="" --rm -it debian:stable /bin/bash` in most instances you can just alias docker to podman and carry on. It uses OCI formatted images just like docker and uses the same registry infrastructure that docker uses.

Installing `podman-docker` will do the aliasing for you.

Re: Fly To Podman: a script that will help you to migrate from Docker

#7

Post by wink » Fri, Feb 21, 2025, 1:38 PM UTC

pzmarzly wrote: post #5

MrThoughtful wrote: post #3

I never tried Podman. I guess the benefit is that it runs on demand and not as a always on demon? How does one install podman on Debian and how does one get a Debian image to run inside podman?

Runs on demand, doesn't require root, can be nested, usually uses newer and simpler primitives (e.g. a few nftables rules in Podman vs iptables spaghetti in Docker). In my experience it is ~90% compatible with Docker. The author explains the practical differences in the blog post https://www.edu4rdshl.dev/posts/from-docker-to-podman-full-m... It is usually easier to install - most distros ship relatively recent versi…

Careful, the version in Debian 12 is old and apparently just barely predates the "good" versions.

I had so many problems that I went back to Docker, because current Podman didn't seem to be trivially installable on Debian 12.

Re: Fly To Podman: a script that will help you to migrate from Docker

#8

Post by exceptione » Fri, Feb 21, 2025, 1:45 PM UTC

wink wrote: post #7

pzmarzly wrote: post #5

Earlier quoted context omitted.

Runs on demand, doesn't require root, can be nested, usually uses newer and simpler primitives (e.g. a few nftables rules in Podman vs iptables spaghetti in Docker). In my experience it is ~90% compatible with Docker. The author explains the practical differences in the blog post https://www.edu4rdshl.dev/posts/from-docker-to-podman-full-m... It is usually easier to install - most distros ship relatively recent versi…

Careful, the version in Debian 12 is old and apparently just barely predates the "good" versions. I had so many problems that I went back to Docker, because current Podman didn't seem to be trivially installable on Debian 12.

In general, if one is happy to run very old versions of software Debian can be your driver. If not, you are in for pain in my experience. (That is also why Ubuntu as default Linux is a tragedy, old bugs and missing features mean that it is not really attractive to officially support Linux for vendors.)

Re: Fly To Podman: a script that will help you to migrate from Docker

#9

Post by 2OEH8eoCRo0 » Fri, Feb 21, 2025, 1:54 PM UTC

MrThoughtful wrote: post #3

I never tried Podman. I guess the benefit is that it runs on demand and not as a always on demon? How does one install podman on Debian and how does one get a Debian image to run inside podman?

apt install podman

podman run -it debian bash

Re: Fly To Podman: a script that will help you to migrate from Docker

#10

Post by vednig » Fri, Feb 21, 2025, 1:57 PM UTC

Just read the source code.

Script does almost all of the things required for the "existing docker containers", migrating networks, blocks, restart mech,etc, that leaves out just one thing migrating any other third party script utilizing docker to podman based instructions. This would highly improve the experience. Goodluck