Kubernetes PVC for daemonsets

August 1, 2019 162 views
Kubernetes CentOS

I have a 1 master two slave kubernetes architecture setup. So when I am creating a daemonset workload with busybox image which just generates some random logs, the container gets created in the first node (slave1) only. The (slave2)
container says ContainerCreating.

I have tried changing the PVC's specs.accessModes: to ReadWriteMany.

Do I need to do any additional changes in order to get the pods running in both the slave nodes ?

Further: I'll be backing up the data generated by these into NFS

3 Answers

Hi,

What storageclass are you using on the PVC?
ReadWriteMany is only supported by a small selection of classes.

eg. DigitalOceans blockstorage don't support RWM (yet).

As @ojna mentioned DO block storage doesnt support RWM and the symptom describes usually is what happens, if that is the type of PVC claim you are using you need a different class.

Hi,

As the other responses have already mentioned, DOKS pvc's by default rely on DO's Block Storage product. In doing so, we inherit the same storage limitations of that product. You can see these limitations documented here:

https://www.digitalocean.com/docs/kubernetes/overview/#persistent-data
https://www.digitalocean.com/docs/kubernetes/overview/#limits

You can also create pvc's using your own storageclasses if you have other means of providing storage to the cluster. The limitation discussed above is not as much a DOKS limitation as it is a DO Block Storage limitation.

Hope this helps!

Regards,

John Kwiatkoski
Senior Developer Support Engineer

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