Unable to connect with telnet, ssh, ftp, etc...

djlerman · 09-05-2007, 12:46 PM

I Have a redhat linux machine that locked up.

Unable to connect to machine with telnet, ssh or ftp. Services going out of the machine webserver, mysql, mail are working.

2 questions:
1) how to I gain access back to the machine?
2) what log or files do I look at to troubleshoot and fix the machine?

This has happened a few times. A reboot regains access for a bit. Since the machine is in a data center rebooting is not the best option for regaining access.

Thanks,
~D

giganet · 09-05-2007, 03:13 PM

Providing you have physical access to the server you should be able to open a terminal- Do you have physical access and can you open a terminal?

Make sure and check 'hosts.allow' that it contains:

Code:

ALL: ALL: allow

Next check 'hosts.deny' that it contains:

Code:

ALL: ALL: deny

I would then check my firewall, run 'iptables -L' and see if your IP you are SSHing from is being blocked.

Sometimes SSH access can be restored by 'stopping' | 'starting' your firewall too.

You may just have to go with a reboot though???

Hope this helps in some way?

Regards