[Discussion] Consider backporting v3 shim API support to containerd 1.7

[henry118]

Hi,

I'd like to start a discussion about potentially backporting v3 shim API support to containerd 1.7. This is related to the compatibility challenges we're seeing with the new runc shim that ships with containerd 2.0.

Currently, when users upgrade to containerd 2.0, the bundled runc shim uses the new v3 API. While containerd 2.0 maintains backward compatibility by supporting v2 API shims, the reverse is not true - containerd 1.7 cannot communicate with v3 API shims. This creates a challenging situation for users who need to downgrade from 2.0 to 1.7 while having active containers, as it could result in orphaned containers and process leaks.

Would anyone be interested in considering a patch for containerd 1.7 that adds support for the v3 shim API? This would provide users with a more robust upgrade/downgrade path between 1.7 and 2.0 versions.

Looking forward to hearing your thoughts.

Thanks.