Question about HA active/standby with hard-wired failover
I am going to deploy F5 Big IP systems including two 3900 LTMs (v10) in real world. Everything is fine with LTM VE on VMware when using active/standby with network failover method and VLAN fail-safe. I have read a statement about combining network failover and hard-wired failover: (tmos management guide 10.1)
You use network failover in addition to hard-wired failover. Even with
serial cable failover configured, communication through network failover
is required for certain features to function properly, for example, the
communication that occurs over the network during failover mirroring.
I have three questions about active/standby
1. Which type of communication does the statement indicate?
2. In the case of active unit's VLAN down, if using VLAN fail-safe how does standby unit know to failover to active? through communication of network failover pair or hard-wired failover or configsync ?
(There are three areas to specify three pairs address: network failover, network mirroring, configsync.)
3. Are there any messages exchanged on serial cable or just voltage?
In conclusion, With active/standby, beside to use hard-wired failover with VLAN fail-safe and network mirroring, is it necessary to enable network failover? does it work without defining network failover address pair?
Thanks and Best Regards