OK, here is the reason and the solution:
Node2 - Configuration - Network: somehow the IP Adresses from the 10gbit NICs were not in there. I just added them and the resync started a second later.

Quick Update: I recreated the Quorum drive HA Target with Replication Manager. On Node1 the 10gbit NIC does not Show up - so I can't choose them for Synchronisation (of course). Any idea why the NIC isn't recognized anymore on Node1? Ping and other communication works through the 10gbit NIC between ...

Hello and good morning! (this is a follow-up Forum Post to the already sent ticket: Case # 00008043) We are using 2 nodes with Native SAN for Hyper-V (Version 6.something) NODE1 had a power failure today. Now it is back online, but it does not "see" the sync channel (red cross) and so we c...