PVE 6.4 to 7.0 update, DRBD no longer works on updated node

[WalterH]

I have a 3 node cluster and one node updated from 6.4 to 7.0. For the Linbit controller and DRBD I use this repository: "deb http://packages.linbit.com/proxmox/ proxmox-7 drbd-9.0 ". I followed all the steps in https://pve.proxmox.com/wiki/Upgrade_from_6.x_to_7.0 and had no visible errors during the update.
Since the update the DRBD devices are not created on this node. /dev/drbd does not exist and "drbdadm status" reports:

drbdadm status
/var/lib/linstor.d/vm-301-disk-1.res:28: Parse error: 'disk | device | address | meta-disk | flexible-meta-disk' expected, but got 'node-id'

But the *.res files are identical on all nodes. "drbdadm status" on the non-updated node reports all devices in sync.

Any idea how to get the DRBD active again on this node with PVE 7.0?

 

[WalterH]

To answer my own question.
drbd-dkms needs internet access via port 2020 to: https://drbd.io:2020.
I added the port 2020 exception to the firewall and reinstalled drbd-dkms. Now the DRBD kernel extension is active and DRBD works again in the cluster.