SSH to FTD via management interface

[Turbo727]

I am unable to ssh to any of my FTD firewalls via their management (diagnostic) interface. The ssh login screen popped up but all of them say access denied. I am very sure the password is correct, even tried a different account, it didn't work too. 

is there anything special I overlooked?

[manabans]

From the console login try to check these two outputs on clish mode, accordingly further troubleshooting action needs to be taken,

> show ssh-access-list
> show user

Outputs from one of my lab FTD,

[tvotna]

Diagnostic interface and management interface are two different things. SSH access via diagnostic interface is not supported and doesn't work beginning from FTD 6.1, when converged CLI was introduced. There were plans to get rid of FTD diagnostic interface in 7.x, because diagnostic interface is nothing but a confusion, but they haven't materialized (yet?).