Hi,
Seeking help from community on ESXi 6.5 network connectivity issue.
We initially had 6 hosts (ESX 6.0) with LACP (LAG with 4 uplinks) on vCenter 6.0. We installed new vCenter 6.5 and have moved 4 hosts on to it with 4 up-links without LACP. Though we are not using LACP on vCenter 6.5 but the vDS configurations were imported from old vCenter 6.0 which uses LACP and we reconfigure new vDS accordingly. Host migration worked well however now after few days we have started experiencing issues with networking. Randomly the Hosts becomes unresponsive and losses network connectivity. So far we have experienced the issue on 3 out of 4 hosts.
On some occasions restarting management network brings back the host online and sometime it doesn't, when it doesn't than we have to restart the host. We have 1 vmkernel adapter for management where we have IPv4 address and 2 vMotion vmkernel adapter where we have IPv6 address. We have also noticed that sometime even restarting the management network only brings the IPv4 stack online as the host becomes responsive however when DRS does vMotion using IPv6 stack on to that host the vMotion fails. Rebooting the host gets the vMotion to work.
When we migrated we imported the vDS which had LACP configurations though we later deleted the vDS and created new vDS and configured all port groups and other settings. When my colleague migrated the hosts he installed 2 of the ESXi from scratch and upgraded the other 2 from 6.0 to 6.5.
We have checked our physical switch configuration and didn't see anything unusual there. The leftover 2 hosts out of total 6 are still in 6.0, connected to the same switches and so far we have not experience any issues in old vCenter. We are unable to figure out what is wrong here, is it some previous LACP configuration somehow stuck in new vCenter database or on the host which we upgraded or is it possibly some bug.
We would appreciate comments and help on this issue. Thanks in advance.
Prabhash
