FTD HA Standby IP Addresss

[taro75]

I am settings up FTD2110 in HA using FDM (web console). Is it mandatory to define standby IP address for each interface in HA?

If I have to monitor both firewalls in NMS, can I achieve this by assigning standby IP address?

[MHM Cisco World]

Yes 

You need to config IP for standby unit interfaces 

[Rob Ingram]

@taro75 it's not mandatory, but you can only monitor an interface if you configure standby IP addresses for it.

https://www.cisco.com/c/en/us/td/docs/security/firepower/710/fdm/fptd-fdm-config-guide-710/fptd-fdm-ha.html

Configure Standby IP and MAC Addresses

When you configure your interfaces, you can specify an active IP address and a standby IP address on the same network. Although recommended, the standby address is not required

[taro75]

OK, that means if I have to monitor both firewalls on NMS (network monitor systems) I can achieve this by defining standby IP address. Am I correct?

[Rob Ingram · Accepted solution]

@taro75 correct, you'd need a standby IP address to monitor the FTD via NMS.

"Without a standby IP address, the active unit cannot perform network tests to check the standby interface health; it can only track the link state. You also cannot connect to the standby unit on that interface for management purposes."  from the same link above.