On Jelastic, I was randomly getting the following volume errors when creating a new environment or scaling horizontally.
"Mount to exported directory /xxx/yyyy is forbidden"
"mount.nfs: access denied by server while mounting ... RPC connection: 124 "
"mount.nfs: connection timed out ..."
For me, fix was to check all volume configs from JPS, the configuration problem was on a different volume than the error in logs described, so it was a bit misleading. (I had a mismatch on volumes and volumeMounts).