Active was down, Standby took over, then Active went up, conflict happened.

Hi,

Of course you need to check "network failover", as you told your equipment are located in different location so I suppose you don't use serial cable. you use HA (Network failover trough you HA vlan).

I think that communication trough F5_A and F5_B trough the HA vlan did not work, probably a network problem between the 2 members trough the vlan that you set for network failover.

I advise you to add an additional vlan and/or use admin network additional. as if there is a network problem through your HA vlan you will still be able to communicate through another network or management interface.

Hope it will help you.

regards,