Take the 2-minute tour ×
Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Following the process I've used in other environments, I've tried setting-up shared keys between my Mac and my CentOS 4 webserver. I've seen the same problem with my older Ubuntu 7.10 workstation trying to connect via keys to the same webserver.

I have tried both dsa and rsa keytypes (sshkeygen -t <type>).

The sshd_config file on my webserver seems to be allowing key-based logins:

RSAAuthentication yes
PubkeyAuthentication yes
AuthorizedKeysFile      .ssh/authorized_keys

And my .ssh/authorized_keys has my dsa and rsa keys added.

Where should I be looking for what to change next to make key-based logins "Just Work™"?

Is it related to the line,

#UseDNS yes

and sshd is trying to do a reverse-lookup on my IP, but cannot because it's NAT'd?

share|improve this question
1  
ssh -v to get verbose diagnostics could help pin down the problem. –  coneslayer Apr 14 '10 at 17:05

4 Answers 4

up vote 5 down vote accepted

~/.ssh/ permissions should be set 0700, and the contents should be 0600.

Also, permissions on ~/ must be 0755 or less; that is, it cannot be writable by any other users.

share|improve this answer
    
Aha! Similar to permissions requirements for .forward files. Thanks! –  warren Apr 14 '10 at 17:26

This Ubuntu page on SSH Keys is good reading (look at Troubleshooting).

share|improve this answer

add some -v option when you initiate your ssh connection as

ssh <user>@<host> -vvv 

If ever you have the admin rights to the server, you could also strace -f -p SSHD_PID your sshd

Both of them will give you a bunch of info....

share|improve this answer

CentOS or Ret Hat maintain old versions of packages, so I think this is an issue with, say OpenSSH 5 connecting to older versions.

If I recall, you probably need to have a file called authorized_keys2 instead of just authorized_keys on the server end.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.