Switch port in blocking state
We have a client installation with two Hyper-V servers on an 1920-24HPv2, each of them with two NICs with LACP (dynamic, based on Windows Server setting). After working fine for weeks, one of the servers now continuously loses the LACP-state and gets completely disconnected by the switch without any obvious reasons. The LACP-Port goes to "blocking" state without any further entries in the event logs and no visible way to set back that state somehow (manually) over Nebula. The only way to bring the server back up is to disable one of the team NICs. Afterwards the server is immediately reachable again and also LACP is working file for a certain while when re-adding the second NIC to the Team, although the port stays in blocking state. The second (absolutely identically configured) server does not have / cause this issue.
Now, the questions are:
- How can we find out, what causes the blocking (event logs, debug, ...)?
- How can we manually unblock the port group without restarting the switch over Nebula?
- Can the issue have somthing to do with different MAC addresses coming for the Hyper-V-Host and the VMs over the teamed NIC?
- Why don't teamed NICs appear correctly in the client list(s)? When using the NICs without the Windows Server Teaming mode the MAC addresses of each of the NICs appear correctly. After adding teaming on the two NICs (with a different MAC) there is no more entry in the client list for the servers, neither for the Hyper-V host or one of its NICs, nor for the VMs "behind" it.