fix: nydus-snapshotter can not run cause of failing of postStart hook

[cheriL]

nydus-snapshotter can not run cause of failing of postStart hook when containerd config is disabled.

events:

  Warning  FailedPostStartHook  28s (x4 over 2m46s)  kubelet            Exec lifecycle hook ([/bin/sh -c # currently, without host pid in container, we can not nsenter with pid and can not invoke systemctl correctly.
nsenter -t 1 -m systemctl -- restart containerd.service
]) for Container "nydus-snapshotter" in Pod "nydus-snapshotter-kg8fs_nydus-snapshotter(6959e4c6-957e-4065-a7d9-b199c90a6535)" failed - error: command '/bin/sh -c # currently, without host pid in container, we can not nsenter with pid and can not invoke systemctl correctly.
nsenter -t 1 -m systemctl -- restart containerd.service
' exited with 127: nsenter: can't execute 'systemctl': No such file or directory
, message: "nsenter: can't execute 'systemctl': No such file or directory\n"
  Normal  Killing  28s (x4 over 2m46s)  kubelet  FailedPostStartHook

[gaius-qi]

@cheriL Please fix lint.

[cheriL]

@gaius-qi done

[adamqqqplay]

Thanks for your fix. I have a small question, can nydus-snapshotter work properly when containerd config is disabled?

[cheriL]

Thanks for your fix. I have a small question, can nydus-snapshotter work properly when containerd config is disabled?

@adamqqqplay Actually, I'm new to nydus and still testing it. The main reason for this change is that I don't want to change the config of containerd by injecting when the daemonset pod starting. And would we consider separating the hostpid and containerd config injection?

[cheriL]

@adamqqqplay I started the nydus daemon pod (with hostPid=true), and configured /etc/containerd/config.toml manually, but still encountered this problem with nydus image:

• ✅ busybox:1.32 (traditional oci image)
• ✅ busybox:1.32-esgz (nerdctl -n k8s.io image convert --estargz --oci busybox:1.32 busybox:1.32-esgz)
• ❌ busybox:1.32-nydus (nerdctl -n k8s.io image convert --nydus --oci busybox:1.32 busybox:1.32-nydus)

Event:

Warning  Failed          13m (x12 over 15m)  kubelet  Error: failed to create containerd container: error unpacking image: failed to extract layer sha256:49de949245b76bb0e2451821fb63dfd2c349decfd047e6a158a20a58a47e08c8: failed to get stream processor for application/vnd.oci.image.layer.nydus.blob.v1: no processor for media-type: unknown

nydus-snapshotter version: v0.13.3
nydus inside pod: v2.1.5

[root@worker12 ~]# ctr plugins ls | grep nydus
io.containerd.snapshotter.v1          nydus                    -              ok

[adamqqqplay]

@adamqqqplay I started the nydus daemon pod (with hostPid=true), and configured /etc/containerd/config.toml manually, but still encountered this problem with nydus image:

• ✅ busybox:1.32 (traditional oci image)
• ✅ busybox:1.32-esgz (nerdctl -n k8s.io image convert --estargz --oci busybox:1.32 busybox:1.32-esgz)
• ❌ busybox:1.32-nydus (nerdctl -n k8s.io image convert --nydus --oci busybox:1.32 busybox:1.32-nydus)

Event:

Warning  Failed          13m (x12 over 15m)  kubelet  Error: failed to create containerd container: error unpacking image: failed to extract layer sha256:49de949245b76bb0e2451821fb63dfd2c349decfd047e6a158a20a58a47e08c8: failed to get stream processor for application/vnd.oci.image.layer.nydus.blob.v1: no processor for media-type: unknown

nydus-snapshotter version: v0.13.3 nydus inside pod: v2.1.5

[root@worker12 ~]# ctr plugins ls | grep nydus
io.containerd.snapshotter.v1          nydus                    -              ok

@cheriL I think your containerd configuration may be overwritten by /etc/containerd/config.toml in kind. Maybe you can remove the field in extraMounts.

      - hostPath: ./config.toml
        containerPath: /etc/containerd/config.toml

[cheriL]

@adamqqqplay My k8s is not set up by kind, the reason is weired that the image converted by nerdctl image convert --nydus didn't work(nerdctl v1.7.0).

[adamqqqplay]

LGTM, thanks!