Multiple SystemD errors during startup after upgrade from PVE 3.4

[acidrop]

Hello list,

I've upgraded a standalone node from PVE 3.4 to 4.1 by following the guide in Wiki (https://pve.proxmox.com/wiki/Upgrade_from_3.x_to_4.0).

Everything went smooth until the point that I restarted the node.
During startup I'm getting the following message which is flooding the screen:

systemd-journald[296]: Failed to forward syslog message: Connection refused

After waiting a long time (the message above still continues to flood the screen), I'm being prompted with the following:

Give root password for maintenance (or type Control-D to continue):

If I press Ctrl+D the boot process continues and finally boots PVE normally.
I can access web gui, start the vms etc.

From webgui -> syslog I get this repetitive entry but I suppose that is due to the watchdog service running:

Mar 03 00:51:58 proxmox2 systemd[1]: systemd-journald.service: Got notification message from PID 296 (WATCHDOG=1...)
Mar 03 00:51:58 proxmox2 systemd[1]: systemd-journald.service: got WATCHDOG=1
Mar 03 00:52:08 proxmox2 systemd[1]: Got notification message for unit systemd-logind.service
Mar 03 00:52:08 proxmox2 systemd[1]: systemd-logind.service: Got notification message from PID 2831 (WATCHDOG=1...)
Mar 03 00:52:08 proxmox2 systemd[1]: systemd-logind.service: got WATCHDOG=1

Can you please advise what I can do to avoid pressing Ctrl+D during the boot process?
I'm assuming that it must be a startup service which is failing but I'm unable to trace which exactly is that.

I'm attaching the full log if anyone can shed a light would be great.

P.S
Please note that this was a Debian Wheezy machine (with PVE repos).

Thank you,