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Cannot connect to ssh server

Posted on 2014-07-21
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396 Views
Last Modified: 2014-09-07
I am having trouble connecting to my ssh server. It responds with a lengthy error message about no network etc. but it is the last message that concerns me:

   
Sometimes, such troubles can be caused by a misconfigured firewall.

How can I check the firewall if I cannot connect to ssh? I am running plesk 11.5 control panel and CentOS 6. Is this something I can do from plesk?

I can see that the firewall in plesk is set to allow all for ssh, but I cannot see way to disable the firewall to test ssh connection. Can this be done from plesk?

It is driving me absolutely bananas and I would be grateful if someone could shed some light as to how I can proceed.
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Comment
Question by:peter-cooper
12 Comments
 
LVL 14

Expert Comment

by:comfortjeanius
ID: 40209674
What is the output of this this command as root privileges:
Type:
iptables -L

Open in new window


Plus did you input to accept connection with this command:
Type:
iptables -A INPUT -p tcp --dport 22 -j ACCEPT

Open in new window

0
 

Author Comment

by:peter-cooper
ID: 40209770
Thank you for your comment. However, I cannot connect with ssh so cannot run any commands. Can I do from plesk?
0
 
LVL 40

Expert Comment

by:omarfarid
ID: 40209941
Can you run ssh -v command and see what messages you get? the displayed messages will give clue to what could be the problem.

Also, you could check with system admin (root) if sshd is running on the server or not.
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LVL 5

Expert Comment

by:Sean Jackson
ID: 40209950
Do you not have console access to the server?
0
 

Author Comment

by:peter-cooper
ID: 40210961
I cannot see from with plesk where that app is. I have the ssh java term installed.
0
 
LVL 9

Expert Comment

by:Sandeep Gupta
ID: 40213794
You need to get console of the firewall and need to check if ssh is dis-allowed there.
0
 

Author Comment

by:peter-cooper
ID: 40216467
@Sandeep Sorry, I do not understand your comment. Thanks
0
 
LVL 5

Expert Comment

by:Sean Jackson
ID: 40217447
Are you able to access the box you're trying to work on directly?  I.E. -- Without using Plesk?
0
 

Author Comment

by:peter-cooper
ID: 40217470
No I am on dynamic cloud server with 1and1.
0
 
LVL 5

Expert Comment

by:Sean Jackson
ID: 40217488
Ugh.

Ok, then start with the box you're coming from.  Check your local firewall.  If there is none, check iptables on the box.  

If you have no other options, maybe fire up some packet captures and see what's happening in WireShark.

Start down these paths, and then let us know what you're finding.
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LVL 27

Accepted Solution

by:
skullnobrains earned 500 total points
ID: 40265077
give the complete error message. this can be caused by many things, and the machine's local firewall is quite unlikely (but you can make sure port 22 is open to the wan)

on idea could be the "password" authentication mathod which is deactivated in most distributions and used by quite a few ssh clients
0
 

Author Closing Comment

by:peter-cooper
ID: 40308464
Many thanks
0

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