* Add readWriteOncePod backupPVC config to enable mount-level SELinux labeling
On SELinux-enabled clusters the kubelet recursively relabels every file of
the backupPVC at mount time, which can take hours on volumes with a high
file count. Kubernetes avoids this when the volume is ReadWriteOncePod and
the CSI driver advertises SELinux mount support, by mounting with
-o context= instead.
Add an opt-in per-storage-class 'readWriteOncePod' backupPVC config option
that creates the backupPVC with the ReadWriteOncePod access mode and sets
the backup pod's SecurityContext.SELinuxChangePolicy to MountOption. It is
mutually exclusive with 'readOnly', which takes precedence.
Fixes#9873
Signed-off-by: Shubham Pampattiwar <spampatt@redhat.com>
* Add changelog file
Signed-off-by: Shubham Pampattiwar <spampatt@redhat.com>
* Do not set SELinuxChangePolicy for the backup pod
Live testing on OCP 4.22 (k8s 1.35) showed that setting
SecurityContext.SELinuxChangePolicy to MountOption makes backup pod
creation fail outright when the SELinuxMount feature gate is disabled,
which is the default on current clusters:
Pod is invalid: spec.securityContext.seLinuxChangePolicy:
Unsupported value: "MountOption": supported values: "Recursive"
The field is also unnecessary. For ReadWriteOncePod volumes the kubelet
already performs mount-level SELinux labeling via the
SELinuxMountReadWriteOncePod feature gate, which has been on by default
since k8s 1.28. Setting the backupPVC access mode to ReadWriteOncePod is
sufficient on its own, and is portable to clusters where the broader
SELinuxMount gate is still off.
Verified on-cluster that the backupPVC is mounted with
context="system_u:object_r:container_file_t:s0:c22,c28" instead of the
recursive seclabel mount used without the flag.
Signed-off-by: Shubham Pampattiwar <spampatt@redhat.com>
---------
Signed-off-by: Shubham Pampattiwar <spampatt@redhat.com>
Shubham PampattiwarandGitHub
63fbf20cc5