[wellylug] What can cause a slow login?

[Enkidu]

On Tue, 23 Nov 2004 13:35:29 +1300 (NZDT), you wrote:

>
>
>On Tue, 23 Nov 2004 michael at diaspora.gen.nz wrote:
>> PAM & DNS.  I saw this sort of problem (ls also worked very quickly, but
>> ls -l didn't -- LDAP was also involved, looking up usernames) on a Redhat
>> box that was doing DNS lookups for ::1, the IPv6 address for localhost,
>> and getting 30 second timeouts from the DNS server it was using.
>>
>> If you do suspect DNS, login as root, use nohup and tcpdump to capture
>> all traffic on port 53; something like:
>>
>>    nohup tcpdump -i eth0 -s 1500 -o /tmp/logfile port 53
>>
>> logout, log back in again, and then use Ethereal to load up the logfile
>> and see if there is anything suspicious.
>
>That reminds me - I once had an issue on a Redhat 9 server where PAM was 
>causing SSH logins to take several seconds to complete. This wasn't too 
>bad for interactive shell sessions, but it completely killed CVS-over-ssh 
>performance (using key-pairs).
>
How d'you diagnose PAM problems?

Cheers,

Cliff
-- 

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