Quick summary - I have 1 user in particular who for some reason cannot login via SSH to my server. I have 2 other users that can login with no problems. This problem didn't manifest until I upgraded my Slackware install from 10.2 to 11. There were some "issues" ( ) with that upgrade, but I thought I had worked them out... guess not

More detail:
I have 2 machines, one the server, one a client. Both these machines have a user called "pat". I'm logged into the client machine as "pat", and I'm trying to ssh to the server as "pat" as well: "pat@client: ssh pat@sshserver". It gets to "password" authentication, but my password is rejected. If I try to login as a different user: "pat@client: ssh user2@sshserver", I have no problems at all - user2's password is accepted just fine.

So - technically I CAN login to my ssh server (I know, I can just su to "pat" once I'm there) but I'm going nuts trying to figure out why I can't ssh in as that one user... If you want the ssh -v output, I can add that, but it doesn't really seem to tell a whole lot (i.e. it looks the same regardless of which user I'm trying to ssh in as...)

One final (probably dumb/obvious) question: Could this just be some weird problem with the "pat" user? Would regenerating this user have any effect? If so, how would I make sure that I don't lose the home directory or any permissions related to that user's uid?

Thanks in advance,

Could you post the exact error message you get when you are denied access?

On sshserver, look at the file "/home/pat/.ssh/known_hosts" and look for an entry that begins with "<client machine name>,<client machine ip address>" that match your client machine. Let me know what you find.

Maybe I'm way off here, but when SSHing from linux, don't you have to specify what user you want to log in as with the "-l" switch, else it defaults to root? Try using your root password to that machine and see if it works. If so, that might be your issue.

Ok - I don't see an entry for the client machine in "/home/pat/.ssh/known_hosts" - I do see the entries for the sshserver machine itself, however. They match the ips and names in my /etc/hosts file. In addition, I don't see any "known_hosts" files in the other users' .ssh directories (e.g. "/home/user2/.ssh")

Thanks,

Just as a test you could try to rename the "/home/pat/.ssh/known_hosts" and then try to ssh again. If it doesn't work you can always put it back.

Yeah, just tried that. In fact, I renamed the entire .ssh directory entirely. Restarted SSHD. Still no luck. I'm stumped. Here's another weird thing - if I ssh in as "user2" , then do an "su - user3", I'm asked for user3's password, as expected. If I "su - pat" instead, I'm NOT asked for pat's password. This holds for any user I ssh in as. I'm beginning to suspect this isn't SSH related at all, except for the fact that I can physically login to the machine itself as "pat" with no problems. Are there any groups a user can belong to that might cause this behavior? "pat" is not a member of "root", but it is a member of several other groups. The other 2 users are only members of "users".

[SOLVED] - I reset the password for the user "pat". SSH logins work as expected now, as well as "su - pat". If possible would like to know an explanation for what might have happened.

Thanks for the help.

Either the password hash for "pat" got corrupted on the server, or the password was removed entirely. If you could su to pat w/o a password, then it was the latter. If su to pat failed, then it was the former. SSH will prevent logins with null passwords by default.