Podman中的Podman，类似于Docker中的Docker？ 标准播客 Podman在Podman中

编程问答 2022-06-06

问题描述

是否可以在Podman中运行Podman，类似于在Docker中运行Docker的方法？

这是我的Dockerfile的一个片段，该片段强烈基于another question：

FROM debian:10.6

RUN apt update && apt upgrade -qqy && \
    apt install -qqy iptables bridge-utils \
                     qemu-kvm libvirt-daemon libvirt-clients virtinst libvirt-daemon-system \
                     cpu-checker kmod && \
    apt -qqy install curl sudo gnupg2 && \
    echo "deb https://download.opensuse.org/repositories/devel:/kubic:/libcontainers:/stable/Debian_10/ /" > /etc/apt/sources.list.d/devel:kubic:libcontainers:stable.list && \
    curl -L https://download.opensuse.org/repositories/devel:/kubic:/libcontainers:/stable/Debian_10/Release.key | sudo apt-key add - && \
    apt update && \
    apt -qqy install podman

现在尝试一些测试：

$ podman run -it my/test bash -c "podman --storage-driver=vfs info"
... (long output; this works fine)

$ podman run -it my/test bash -c "podman --storage-driver=vfs images"
ERRO[0000] unable to write system event: "write unixgram @000ec->/run/systemd/journal/socket: sendmsg: no such file or directory" 
REPOSITORY  TAG     IMAGE ID  CREATED  SIZE

$ podman run -it my/test bash -c "podman --storage-driver=vfs run docker.io/library/hello-world"
ERRO[0000] unable to write system event: "write unixgram @000ef->/run/systemd/journal/socket: sendmsg: no such file or directory" 
Trying to pull docker.io/library/hello-world...
Getting image source signatures
copying blob 0e03bdcc26d7 done  
copying config bf756fb1ae done  
Writing manifest to image destination
Storing signatures
ERRO[0003] unable to write pod event: "write unixgram @000ef->/run/systemd/journal/socket: sendmsg: no such file or directory" 
ERRO[0003] Error preparing container 66692b7ff496775499d405d538769a078f2794549955cf2409fcbcbf87f42e94: error creating network namespace for container 66692b7ff496775499d405d538769a078f2794549955cf2409fcbcbf87f42e94: mount --make-rshared /var/run/netns Failed: "operation not permitted" 
Error: Failed to mount shm tmpfs "/var/lib/containers/storage/vfs-containers/66692b7ff496775499d405d538769a078f2794549955cf2409fcbcbf87f42e94/userdata/shm": operation not permitted

我还尝试了other question的建议，并通过了--cgroup-manager=cgroupfs，但没有成功：

$ podman run -it my/test bash -c "podman --storage-driver=vfs --cgroup-manager=cgroupfs run docker.io/library/hello-world"
Trying to pull docker.io/library/hello-world...
Getting image source signatures
copying blob 0e03bdcc26d7 done  
copying config bf756fb1ae done  
Writing manifest to image destination
Storing signatures
ERRO[0003] unable to write pod event: "write unixgram @000f3->/run/systemd/journal/socket: sendmsg: no such file or directory" 
ERRO[0003] Error preparing container c3fff4d8161903aaebd6f89f3b3c06b55038e11e07b6b561dc6576ca675747a3: error creating network namespace for container c3fff4d8161903aaebd6f89f3b3c06b55038e11e07b6b561dc6576ca675747a3: mount --make-rshared /var/run/netns Failed: "operation not permitted" 
Error: Failed to mount shm tmpfs "/var/lib/containers/storage/vfs-containers/c3fff4d8161903aaebd6f89f3b3c06b55038e11e07b6b561dc6576ca675747a3/userdata/shm": operation not permitted

似乎需要一些网络配置。我发现下面的项目表明可能需要对网络配置进行一些调整，但是我不知道它的上下文以及它是否适用于此。 https://github.com/joshkunz/qemu-docker

编辑：我刚刚发现了/var/run/podman.sock，但也没有成功：

$ sudo podman run -it -v /run/podman/podman.sock:/run/podman/podman.sock my/test bash -c "podman --storage-driver=vfs --cgroup-manager=cgroupfs run docker.io/library/hello-world"
Trying to pull my/test...
  denied: requested access to the resource is denied
Trying to pull my:test...
  unauthorized: access to the requested resource is not authorized
Error: unable to pull my/text: 2 errors occurred:
        * Error initializing source docker://my/test: Error reading manifest latest in docker.io/my/test: errors:
denied: requested access to the resource is denied
unauthorized: authentication required

        * Error initializing source docker://quay.io/my/test:latest: Error reading manifest latest in quay.io/my/test: unauthorized: access to the requested resource is not authorized

似乎root不能看到我在用户下创建的图像。

有什么想法吗？谢谢。

解决方法

假设我们想在 docker.io/library/alpine 容器中运行ls /。

标准播客

podman run --rm docker.io/library/alpine ls /

Podman在Podman中

让我们在 docker.io/library/alpine 容器中运行ls /，但是这次我们在 quay.io/podman/stable中运行podman 容器。

该命令将如下所示：

podman \
  run \
    --privileged \
    --rm \
    --ulimit host \
    -v /dev/fuse:/dev/fuse:rw \
    -v ./mycontainers:/var/lib/containers:rw \
    quay.io/podman/stable \
      podman \
        run \
          --rm \
          --user 0 \
          docker.io/library/alpine ls

（目录 ./ mycontainers 用于存储容器）

这是一个完整的例子

$ podman --version
podman version 2.1.1
$ mkdir mycontainers
$ podman run --privileged --rm --ulimit host -v /dev/fuse:/dev/fuse:rw -v ./mycontainers:/var/lib/containers:rw   quay.io/podman/stable podman run --rm --user 0 docker.io/library/alpine ls | head -5
Trying to pull docker.io/library/alpine...
Getting image source signatures
Copying blob sha256:188c0c94c7c576fff0792aca7ec73d67a2f7f4cb3a6e53a84559337260b36964
Copying config sha256:d6e46aa2470df1d32034c6707c8041158b652f38d2a9ae3d7ad7e7532d22ebe0
Writing manifest to image destination
Storing signatures
bin
dev
etc
home
lib
$ podman run --privileged --rm --ulimit host -v /dev/fuse:/dev/fuse:rw -v ./mycontainers:/var/lib/containers:rw  quay.io/podman/stable podman images
REPOSITORY                TAG     IMAGE ID      CREATED     SIZE
docker.io/library/alpine  latest  d6e46aa2470d  4 days ago  5.85 MB

如果您忽略了-v ./mycontainers:/var/lib/containers:rw，则可能会看到稍微混乱的错误消息

Error: executable file `ls` not found in $PATH: No such file or directory: OCI runtime command not found error

参考：

dockerkvmpodmanvirtualization