Volumes don't get properly unmounted when container is moved

[discordianfish]

Jan 03 11:54:45 master1 hyperkube[1450]: E0103 11:54:45.242527    1450 reconciler.go:423] Error occured during reconstruct volume from disk: Could not add volume information to actual state of world: failed to get Plugin from volumeSpec for volume "data" err=no volume plugin matched

[klausenbusk]

Is this a frequent issue and did you every pin-point it any further? As I am currently "evaluating" our future setup, I'm wondering if this is stable enough.
I'm also considering writing a flex volume plugin in Go with help from: https://godoc.org/github.com/digitalocean/godo

[discordianfish]

@klausenbusk It didn't happen to me anymore, but I don't do much on the cluster either.
But yes, I agree a volume plugin in Go would be better. I wanted to wait for the new flex volume spec to get finalized. Not sure what the state of this is though.

[sonamsamdupkhangsar]

Hi there,
CoreOS mounts /usr as read-only. So was suggested to create a /etc/kubernetes/kubelet.env with content
KUBELET_ARGS =--volume-plugin-dir=/etc/kubernetes/volumeplugins

However, my pod using the volume remains in ContainerCreating status. Not sure if kubelet knows about the volumeplugins folder. Any suggestion I could try? In my nodes' journal I do see the following error:

4] Failed to add volume "data" (specName: "data") for pod "b8aa6ebc-2a3d-11e7-9199-aa5694166889" to desiredStateOfWorld. err=failed to get Plugin from volumeSpec for volume "data" err=no volume plugin matched

[discordianfish]

@sonamsamdupkhangsar Hrm yeah looks like this is a problem with the kubelet. Never had to change the volume path. Maybe ask the kubernetes folks about it?

[klausenbusk]

@sonamsamdupkhangsar check the kubelet.service file. I'm not sure it use the kubelet.env file. I can check our setup when I get home.

[sonamsamdupkhangsar]

@klausenbusk any chance you can share your find on how to set volume plugins?

[klausenbusk]

@klausenbusk any chance you can share your find on how to set volume plugins?

Hello, I totally forgot it :)

I change the kubelet.service file with my "new-server-init"-script. It should also be doable by hand.

Something like:

extra_arg="--volume-plugin-dir=/etc/kubernetes/volumeplugins"
kubelet_file="/etc/systemd/system/kubelet.service"

ssh $1 -T sudo sed \"\\:kubelet-wrapper: s:$: ${extra_arg}:\" -i "${kubelet_file}"