FMC / FTD Management IP/FQDN Problem

[SmithIT]

We just changed a Module SM-56 on a Chassis 9300. Everything works great, only that now on the FMC the Device has now an IP instead of FQDN under management. All other Modules, and Devices are using FQDN for the Management Address, and it was working before the Modul Change. 

When i change to FQDN (under DEVICES>DEVICE MANAGEMENT>HA DEVICE>DEVICE> the Status changes to red. 

I tested:

• - nslookup on FTD to manager FQDN works
• - nslookup on FMC to manager FQDN works

Can somebody point me to the right direction. It worked before we changed the Module. 

The only thing that has been changed during the Module change is following: Some time ago we changed the Managament IP Setup in the Network, but it looked strange. There where two different Management IP's on the FTD. (See image. in my example: 1.2.3.4 and 11.22.33.44). But it did work with the correct IP (11.22.33.44) and even with the FQDN. Now we have it corrected. Gateway is also correct. But now we have the above mentioned Problem. 

It works when using the IP, but not when using the FQDN. 

Any Idea ?

[Marvin Rhoads]

Check "show network" from the FTD cli to confirm the settings there.

Also, if the replaced SM was an FTD instance that is part of an HA pair, you may need to recreate HA. Check "show failover" and "show managers" from the FTD cli.

[SmithIT]

checked show network, looks as designed. Checked manageres: all good. And indeed we Broke the HA, and it is working again. show failover proves it. All works as designed using Mngmt IP Addresses, but not working with FQDN (but did work before the module change). Any other suggestion ?

[SmithIT · Accepted solution]

For the latest Vulnerabilities, we updated from 7.0.5 to 7.0.6 and see and behold, its working again. Must have been a Bug in 7.0.5.

[Marvin Rhoads]

Thanks for the update. I didn't see a resolved bug specifically for that but it could be that the reload kicked something loose.