How to troubleshoot pts issues in unusual environment?

[alexpdp7]

Hi,

I'm trying to get distrobox/toolbox working inside an LXC container... with rootless podman.

[alex@ws ~]$ podman exec -it 1eb8fbbfe9f4 bash
Error: crun: open /dev/pts/4: No such file or directory: OCI runtime attempted to invoke a command that was not found

Where 1eb... is the container that distrobox/toolbox create. I can also reproduce the same error by creating a container with:

[alex@ws ~]$ podman run -d --mount type=devpts,destination=/dev/pts --userns keep-id --volume /dev:/dev:rslave registry.access.redhat.com/ubi9/ubi:latest sleep infinity
53aa717c1fc562f3b0f363f0ceb4a737fb749ea715295b83b4884955fadbae78
[alex@ws ~]$ podman exec -it 53aa bash
Error: crun: open /dev/pts/4: No such file or directory: OCI runtime attempted to invoke a command that was not found

Any pointers?

Cheers,

Álex

[rhatdan]

Does podman info work?

[alexpdp7]

Sure:

output of podman info

[alex@ws ~]$ podman info
host:
  arch: amd64
  buildahVersion: 1.27.3
  cgroupControllers:
  - memory
  - pids
  cgroupManager: systemd
  cgroupVersion: v2
  conmon:
    package: conmon-2.1.4-1.el9.x86_64
    path: /usr/bin/conmon
    version: 'conmon version 2.1.4, commit: fd49ef99363f06fe6b6ab119070cd95c6cc7c35a'
  cpuUtilization:
    idlePercent: 98.5
    systemPercent: 0.42
    userPercent: 1.08
  cpus: 12
  distribution:
    distribution: '"rocky"'
    version: "9.1"
  eventLogger: file
  hostname: ws.h1.int.pdp7.net
  idMappings:
    gidmap:
    - container_id: 0
      host_id: 1284000001
      size: 1
    - container_id: 1
      host_id: 100000
      size: 65536
    uidmap:
    - container_id: 0
      host_id: 1284000001
      size: 1
    - container_id: 1
      host_id: 100000
      size: 65536
  kernel: 5.15.102-1-pve
  linkmode: dynamic
  logDriver: k8s-file
  memFree: 2005983232
  memTotal: 2147483648
  networkBackend: netavark
  ociRuntime:
    name: crun
    package: crun-1.5-1.el9.x86_64
    path: /usr/bin/crun
    version: |-
      crun version 1.5
      commit: 54ebb8ca8bf7e6ddae2eb919f5b82d1d96863dea
      spec: 1.0.0
      +SYSTEMD +SELINUX +APPARMOR +CAP +SECCOMP +EBPF +CRIU +YAJL
  os: linux
  remoteSocket:
    path: /run/user/1284000001/podman/podman.sock
  security:
    apparmorEnabled: false
    capabilities: CAP_CHOWN,CAP_DAC_OVERRIDE,CAP_FOWNER,CAP_FSETID,CAP_KILL,CAP_NET_BIND_SERVICE,CAP_SETFCAP,CAP_SETGID,CAP_SETPCAP,CAP_SETUID,CAP_SYS_CHROOT
    rootless: true
    seccompEnabled: true
    seccompProfilePath: /usr/share/containers/seccomp.json
    selinuxEnabled: false
  serviceIsRemote: false
  slirp4netns:
    executable: /usr/bin/slirp4netns
    package: slirp4netns-1.2.0-2.el9.x86_64
    version: |-
      slirp4netns version 1.2.0
      commit: 656041d45cfca7a4176f6b7eed9e4fe6c11e8383
      libslirp: 4.4.0
      SLIRP_CONFIG_VERSION_MAX: 3
      libseccomp: 2.5.2
  swapFree: 0
  swapTotal: 0
  uptime: 2h 14m 3.00s (Approximately 0.08 days)
plugins:
  authorization: null
  log:
  - k8s-file
  - none
  - passthrough
  - journald
  network:
  - bridge
  - macvlan
  volume:
  - local
registries:
  search:
  - registry.access.redhat.com
  - registry.redhat.io
  - docker.io
store:
  configFile: /home/alex/.config/containers/storage.conf
  containerStore:
    number: 4
    paused: 0
    running: 3
    stopped: 1
  graphDriverName: vfs
  graphOptions: {}
  graphRoot: /home/alex/.local/share/containers/storage
  graphRootAllocated: 4294967296
  graphRootUsed: 3034841088
  graphStatus: {}
  imageCopyTmpDir: /var/tmp
  imageStore:
    number: 3
  runRoot: /run/user/1284000001/containers
  volumePath: /home/alex/.local/share/containers/storage/volumes
version:
  APIVersion: 4.2.0
  Built: 1677602055
  BuiltTime: Tue Feb 28 17:34:15 2023
  GitCommit: ""
  GoVersion: go1.18.9
  Os: linux
  OsArch: linux/amd64
  Version: 4.2.0

I think it's a combination of the options used (keep user-ns, and the /dev stuff), without these I can podman exec -it.

[alexpdp7]

Interesting, the devpts mount in distrobox/toolbox seems to come from this thread:

containers/toolbox#568

, which is still open. It's weird because distrobox supports Docker, and Docker does not support the devpts mount.

And there's something nagging me; the error about /dev/pts/4 seems to indicate a problem outside the container (because if I create more terminals outside the container, the number goes up). But how this could be? Maybe there's a podman bug that manifests under my weird environment only?