Firepower 2120 lost configuration

[dpditstaff]

We were in the process of finalizing the configuration of a 2120 with the next step being adding it to the FMC.  The registration failed for unknown reasons.  During the process, we restarted the device and subsequently lost all configuration with the exception of the management interface.  It was my understanding the any changes to the Firepower device is saved after deploying unlike the ASAs which require writing the configuration to NVRAM.

Any insight would be appreciated.

[MHM Cisco World]

Did you use deploy after each config ?

[dpditstaff]

Thank you for your reply.  I did "deploy" after each configuration update.  However, apparently, the config was lost when management was transitioned to the FMC.

[MHM Cisco World]

Sorry I was think that you first sucess register ftd to fmc do config then restart' then you see config lost.

Then I check @Marvin Rhoads answer and get issue here you migrate from fdm to fmc that why the config lost.

[dpditstaff]

No worries - I appreciate the response.

[Marvin Rhoads · Accepted solution]

If it was initially configured with FDM (local manager), all of that configuration is lost when registering to FMC. The two management types are mutually exclusive.

[dpditstaff]

Thank you for your reply!!