Go Back   The UNIX and Linux Forums > Homework and Emergencies > Emergency UNIX and Linux Support !! Help Me!!


Emergency UNIX and Linux Support !! Help Me!! Post your urgent questions here for highest visibility. Posting a new thread to this forum requires Bits. We monitor this forum to help people with emergencies, but we do not guarantee response time or answers. This forum is "best effort" only. Members who reply to posts here receive a bonus of 1000 Bits per reply.

Closed Thread    
 
Thread Tools Search this Thread Display Modes
    #1  
Old 04-28-2012
Registered User
 
Join Date: Oct 2010
Posts: 69
Thanks: 18
Thanked 1 Time in 1 Post
SSH operation timed out

This has never happened before, but my laptop is now unable to access any remote servers. I have tried with 3 independent servers that I have access as recently as last week.

I am not asked for my password,


Code:
home:~ x$ ssh -v -p22 user@server
OpenSSH_5.2p1, OpenSSL 0.9.7l 28 Sep 2006
debug1: Reading configuration data /etc/ssh_config
debug1: Connecting to server [194.57.168.xx] port 22.
debug1: connect to address 194.57.168.xx port 22: Operation timed out
ssh: connect to host serverport 22: Operation timed out

What might I have done wrong? I cleared the known_hosts file after I started having this problem. I can see that ssh_config is probably what is causing me this problem

When I ping any of the remote servers I get no response and on cancelling the request I have 100% packet loss.

Any help appreciated!!!!!
Sponsored Links
    #2  
Old 04-28-2012
DukeNuke2's Avatar
Soulman
 
Join Date: Jul 2006
Location: Berlin, Germany
Posts: 5,080
Thanks: 40
Thanked 191 Times in 186 Posts
looks more like a network problem... if you can not ping the server, you most certainly can not ssh to the server...
Sponsored Links
    #3  
Old 04-29-2012
admin_xor's Avatar
Registered User
 
Join Date: Jun 2011
Posts: 450
Thanks: 13
Thanked 77 Times in 74 Posts
As Duke mentioned, it's certainly a network problem. Could be an issue due to network configuration of the laptop or could be possible network admin changed VLANs behind your back and forgot to enable routing among them.

I would rather need a clear picture of your network and the network config of the OS you are running to conclude something.
    #4  
Old 05-01-2012
laz's Avatar
laz laz is offline
Registered User
 
Join Date: May 2012
Location: Draper, VA
Posts: 2
Thanks: 0
Thanked 0 Times in 0 Posts
Tools

Greetings,

As has been previously mentioned, more information about your network topology would probably help in troubleshooting this. That being said, let me toss out a couple situations that might apply to your problem, or if not, maybe they can help get you thinking in the right direction.

First, just because a ping does not succeed does not mean there is a problem. If you are on different subnets or networks, that might be normal. Most networks block ICMP (ping) traffic from entering their networks if not being more restrictive. If however, you have been able to successfully ping before, and now you cannot, then it would seem that there is indeed a network problem and you should contact someone on your network team.

Second, most UNIX and Linux servers use TCP_WRAPPERS to protect network services on their server. This means that in the hosts.allow file, there is most likely an entry allowing you and your computer access via SSH. This is done by allowing your IP address (or subnet perhaps) or hostname access to the system. If by some chance the IP address on your PC has changed (say, by DHCP) that could cause the error you see. Or if they are using a hostname to allow access, it could be a DNS problem if the server you are connecting to cannot perform a reverse DNS lookup on your IP. So there are a couple things to check, make sure your IP hasn't changed and make sure that reverse DNS is working properly for that IP. Plus, the server you are connecting to could be having DNS problems even if DNS in general is functioning on your network.

I hope this helps, please post an update with more information if you are still having problems, or if you find the solution.

Thanks,

Laz
Sponsored Links
    #5  
Old 05-14-2012
chakrapani's Avatar
Registered User
 
Join Date: Sep 2009
Location: Asia
Posts: 170
Thanks: 0
Thanked 5 Times in 4 Posts
As you get error with given command and your SSH command is user@server (I hope it is some server name not IP).

So it is trying to connect to 194.57.168.xx .
Now if ping failed it could that server is down/network is down or Server has ping disabled on n/w or on server or even from your laptop f/w.

Do some basic check
1. Check if you internet connection is good
2. Check if you can connect to another server on same n/w
3. if you have internet working . then try connecting via another server. Some times routes are set bad or shortest connection is down.
4. Call some one on Datacenter and check if server is up or not.
else .. we have a Road block.


Code:
home:~ x$ ssh -v -p22 user@server
OpenSSH_5.2p1, OpenSSL 0.9.7l 28 Sep 2006
debug1: Reading configuration data /etc/ssh_config
debug1: Connecting to server [194.57.168.xx] port 22.
debug1: connect to address 194.57.168.xx port 22: Operation timed out
ssh: connect to host serverport 22: Operation timed out

Sponsored Links
    #6  
Old 05-16-2012
otheus's Avatar
otheus otheus is offline Forum Advisor  
Smartass
 
Join Date: Feb 2007
Location: Innsbruck, Austria
Posts: 2,139
Thanks: 12
Thanked 43 Times in 41 Posts
My hunch: firewall is blocking it.
Sponsored Links
    #7  
Old 05-16-2012
Registered User
 
Join Date: Dec 2010
Location: Yugoslavia
Posts: 225
Thanks: 37
Thanked 9 Times in 9 Posts
Quote:
Originally Posted by DukeNuke2 View Post
looks more like a network problem... if you can not ping the server, you most certainly can not ssh to the server...
not necessarily, firewall could block ICMP but pass ssh.
Sponsored Links
Closed Thread

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

More UNIX and Linux Forum Topics You Might Find Helpful
Thread Thread Starter Forum Replies Last Post
Column operation : cosne and sine operation shashi792 Shell Programming and Scripting 4 09-08-2010 07:59 PM
I/O timed out etcpasswd Solaris 5 08-12-2009 04:34 AM
Timed wait? anjul_thegreat Programming 4 06-29-2007 09:51 AM
connection timed out paschal HP-UX 0 06-15-2007 02:40 PM
in.timed log entries hcclnoodles Solaris 1 12-04-2006 12:40 PM



All times are GMT -4. The time now is 02:37 AM.