Allow mount volume operations to run in parallel for non-attachable
volume plugins.
Allow unmount volume operations to run in parallel for all volume
plugins.
Ensure that kublet marks VolumeInUse before checking if it is Attached.
Also ensures that the attach/detach controller always fetches a fresh
copy of the node object before detach (instead ofKubelet relying on node
informer cache).
Modify attach/detach controller to keep track of volumes to report
attached in Node VolumeToAttach status.
Modify kubelet volume manager to wait for volume to show up in Node
VolumeToAttach status.
Implement exponential backoff for errors in volume manager and attach
detach controller
This commit adds a new volume manager in kubelet that synchronizes
volume mount/unmount (and attach/detach, if attach/detach controller
is not enabled).
This eliminates the race conditions between the pod creation loop
and the orphaned volumes loops. It also removes the unmount/detach
from the `syncPod()` path so volume clean up never blocks the
`syncPod` loop.
This PR contains Kubelet changes to enable attach/detach controller control.
* It introduces a new "enable-controller-attach-detach" kubelet flag to
enable control by controller. Default enabled.
* It removes all references "SafeToDetach" annoation from controller.
* It adds the new VolumesInUse field to the Node Status API object.
* It modifies the controller to use VolumesInUse instead of SafeToDetach
annotation to gate detachment.
* There is a bug in node-problem-detector that causes VolumesInUse to
get reset every 30 seconds. Issue https://github.com/kubernetes/node-problem-detector/issues/9
opened to fix that.
If it does belong to the device then we make sure we mount the mpio device instead of
the raw device.
Heuristics
Login into /dev/disk/by-path/iqn-example.com.2999 -> /dev/sde
Check if sde existsin in /sys/block/[dm-X]/slaves/xx
If it does mount /dev/[dm-x] which will look like /dev/mapper/mpiodevicename in mount
examples/iscsi has more details
- Add volume.MetricsProvider function to Volume interface.
- Add volume.MetricsDu for providing metrics via executing "du".
- Add volulme.MetricsNil for unsupported Volumes.
