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There are two remote servers, 01 and 02. I can ssh to 01 from the local machine, but not to 02 - ssh times out. That timeout happens intermittently, and I cannot correlate it with any activity going on the server or the network.
01 and 02 are on the same subnet.
What's strange is that I can always ssh to 02 from 01 (ssh to 01 from the local machine).

I'm trying to explain why this happens.

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Have you done any troubleshooting? (running the ssh client with -v -- maybe multiple vs for extra effect? Looking at the logs on server #2 and comparing successful tries to failures?) -- You give us literally nothing with which we can help you... –  voretaq7 Jun 22 '12 at 17:47

1 Answer 1

Sounds like you may have a firewall issue somewhere between you and your servers which is causing an issue. A few things to check, are you using DNS names? Does using IP only fix it or have a different outcome? What are the firewall rules like on server 01 and 02 (iptables -nL for Linux). Try running tcpdump on 02 (tcpdump -i eth0 port 22 and not host 01), do you see an inbound connection attempt? Also what are the log files telling you (/var/log/messages, /var/log/secure), anything interesting which would explain what you are seeing? If the firewall rules allow you to ping, what happens when you try to ping the hosts in question?

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Thanks, great suggestions to try –  OutputLogic Jun 22 '12 at 17:56
    
If it were a permanent firewall issue, the ssh from local to 02 would never work. But it does work most of the time (or doesn't work intermittently). The connection in question is between two company branches in N.America and S.East Asia. –  OutputLogic Jun 22 '12 at 18:07

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