Conversation
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Jet Chiang <pokyuen.jetchiang-ext@solo.io> Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
Signed-off-by: Eitan Yarmush <eitan.yarmush@solo.io>
…pagation atelet hostPath-mounts /var/lib/kubelet/plugins to reach the CSI driver sockets. With the default (private) propagation every atelet start copies the node's CSI globalmounts into the container's mount namespace, and kubelet's later unmount of a volume does not reach that copy: the volume's filesystem stays mounted there, the block device (and the LUKS mapper of an encrypted volume) stays open, and the volume can never be unstaged while atelet runs. Observed with Longhorn: NodeUnstageVolume failed forever with "cryptsetup luksClose: Device is still in use" after a pod moved to another node, and the pod could not attach the volume on the new node until atelet was restarted. HostToContainer (rslave) is what CSI node plugins use for the kubelet directories: mounts and unmounts made by kubelet propagate into the container, nothing propagates back. Signed-off-by: Timo Derstappen <teemow@gmail.com>
teemow
added a commit
to giantswarm/substrate
that referenced
this pull request
Sep 15, 2026
EItanya
force-pushed
the
main
branch
5 times, most recently
from
September 20, 2026 14:03
a7701e8 to
300be0c
Compare
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
6 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Problem
atelet hostPath-mounts
/var/lib/kubelet/pluginsto reach the CSI driver sockets. With the default (private) propagation, every atelet start copies the node's CSI globalmounts into the container's mount namespace, and kubelet's later unmount of a volume never reaches that copy. The volume's filesystem — and the LUKS mapper of an encrypted volume — stays open, so the volume cannot be unstaged while atelet runs.We hit this with Longhorn on a cluster running Substrate: after a pod moved to another node,
NodeUnstageVolumefailed forever withcryptsetup luksClose: Device is still in use, and the pod could not attach its volume on the new node until atelet was restarted.Fix
mountPropagation: HostToContainer(rslave) on thekubelet-pluginsvolume mount — what CSI node plugins use for the kubelet directories. Mounts and unmounts made by kubelet propagate into the container; nothing propagates back.Rendered manifests are otherwise unchanged. The change has been running in our Substrate deployment since 2026-09-11.
Prepared with AI assistance, reviewed and tested by the author.