SSH connection slow. Is UsePAM=no safe?

[grixm]

Every time I tried to log on to ssh on my rock-s0 with armbian, there would be a delay of like 5 seconds. I found a solution that fixes this problem. This thread is partly a PSA about this solution, and a question about whether this solution is a good idea or not.

The trick is to change UsePAM=yes , to UsePAM=no , in the /etc/ssh/sshd_config file.

But I heard some people online say this is a bad idea, but I don't understand PAM enough to know why. I am only going to use ssh in a basic password-authenticated, LAN environment. Do I really need PAM? The only side-effect I noticed is that it no longer shows the MOTD when logging in. 

[laibsch]

I don't think I can condone changing a very, very security-relevant part of your setup without fully understanding its implications.  So, it's good you ask here.  I can't answer it off the top of my hat, but maybe somebody else can chime in.  I don't think I would bother for the sake of 5 seconds.  Are you logging in and out all the time?

 

By the way, PAM is short for pluggable authentication module, so you are disabling an authentication mechanism.