FAILED failover: Virtual servers were disabled on standby unit.

I have definitive answers here but maybe some info to help along the way...

 

Were all the pools offline on lb1 or just the ones you mention while others were still green/online? Bigip has built-in snmp trap alerts for pools/pool members marked offline/online, were those received from lb1?

 

Bigip does not continuously log offline status of vs/pools. The down events are logged once at the time they occur only. Monitors should have continued checking every 10 secs even after pools were down so it seems there was some issue (obviously) with lb1 internally or its ability to reach the servers.

 

Regarding the "In sync" status, that refers to the configuration not the status of VS/pools. Each bigip runs monitors independently and the resulting status is not synced/shared with the other bigip. The offline status of VS/pools will not stop a bigip from going active. In other words lb1 going active even though vs/pools were offline is expected behavior. HA groups and/or vlan failsafe features may have altered your experience here.

 

Have you opened a case with F5 support to get any insight they may have?