podman/contrib/rootless-cni-infra

rootless-cni-infra

Infra container for CNI-in-slirp4netns.

How it works

When a CNI network is specified for podman run in rootless mode, Podman launches the rootless-cni-infra container to execute CNI plugins inside slirp4netns.

The infra container is created per user, by executing an equivalent of: podman run -d --name rootless-cni-infra --pid=host --privileged -v $HOME/.config/cni/net.d:/etc/cni/net.d rootless-cni-infra. The infra container is automatically deleted when no CNI network is in use.

Podman then allocates a CNI netns in the infra container, by executing an equivalent of: podman exec rootless-cni-infra rootless-cni-infra alloc $CONTAINER_ID $NETWORK_NAME $POD_NAME.

The allocated netns is deallocated when the container is being removed, by executing an equivalent of: podman exec rootless-cni-infra rootless-cni-infra dealloc $CONTAINER_ID $NETWORK_NAME.

The container images live on quay.io/libpod/rootless-cni-infra. The tags have the format $version-$architecture. Please make sure to increase the version number in the Containerfile (i.e., ROOTLESS_CNI_INFRA_VERSION) when applying changes to this directory. After committing the changes, upload the image(s) with the corresponding tag.

Directory layout

• /run/rootless-cni-infra/${CONTAINER_ID}/pid: PID of the sleep infinity process that corresponds to the allocated netns
• /run/rootless-cni-infra/${CONTAINER_ID}/attached/${NETWORK_NAME}: CNI result
• /run/rootless-cni-infra/${CONTAINER_ID}/attached-args/${NETWORK_NAME}: CNI args