FTP server hanging at PASS, couldn't tell why

anon091 · 04-08-2013, 12:40 PM

Hi everyone. I have a FTP server that was hanging for most users at the PASS part, right after it accepted their username and it was trying to take their password. It would just keep timing out. Because I wasn't sure what to do, I restarted the server, and after it was up for a few minutes, it appeared to be working ok then.

Is there any way I can look through some logs or something to see what might have been causing the issue?

dubnik · 04-09-2013, 07:40 AM

distribution?
name of ftp server ?
some logs ?

anon091 · 04-09-2013, 07:46 AM

RHEL
vsftpd
And that's exactly my question haha

Shmiti · 04-09-2013, 08:04 AM

http://www.centos.org/docs/4/html/rh...ftpd-conf.html
go to section 15.5.7 for logging options, turn on logging and also put a sniffer on the port
tcpdump -vvv -i <interface name> port <port number>

make sure to replace the <interface name> with the host interface the vsftpd is listening on (most likely eth0 / em1) and <port nunmber> would most likely be 21.

In addition, where to you store the users?
host users? ldap? virtual users?

anon091 · 04-09-2013, 08:27 AM

Thanks, I'll read that link. all the users are in /etc/passwd, no ldap.

chrism01 · 04-09-2013, 08:48 AM

You may find hints to the logs here http://www.linuxtopia.org/online_boo...d-conf-opt-log

Shmiti · 04-09-2013, 08:56 AM

check if you are using name cache (nscd service), it may be problematic,
look at the /etc/nsswitch.conf to look at the order of user lookup