Two Active Big IP's in HA mode

is unicast-address on device configured correctly? is network-failover enabled on device-group? is there any useful message in /var/log/ltm?

e.g.

root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list cm device ve11a.acme.local unicast-address
cm device ve11a.acme.local {
    unicast-address {
        {
            effective-ip 200.200.200.11
            effective-port 1026
            ip 200.200.200.11
            port 1026
        }
    }
}

root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list cm device-group dg network-failover
cm device-group dg {
    network-failover enabled
}

unicast addresses are ok. We had a network problem that caused it. network failover is enabled. No log messages that I can tell but I don't really know what to look for.

I don't really know what to look for.

what about grepping sod?

 grep sod /var/log/ltm

are you sure your network failover is ok? have you checked if the port 1026 (i believe) packets are send correctly with tcpdump?

Network failover can be made more robust by directly connecting your LTM's to each other using a straight-through cable, creating a 'peernet' vlan and /30 self-IP addresses (ex. 192.168.255.0/30 = 192.168.255.1 for Unit 1 and 192.168.255.2 for Unit 2), and then using configuring network failover with the peernet self-IP addresses and your management IP addresses. HA groups or VLAN failsafe can then be applied to the production (non-peernet) trunks/vlans to ensure failover occurs when active unit loses connectivity to the rest of the network