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From a Windows Vista client using Cygwin, I am not be able to ssh to a Ubuntu server.

I have two other clients (one Vista and one Windows 7) which can SSH to the server. All three are using Cygwin.

Here are the logs from both sides for the same attempt

Client-> http://pastie.org/3740969

Server-> http://pastie.org/3740960

noel_g
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2 Answers2

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The problem with with a firewall installed on the computer (BlackIce)

Even thought Putty worked correctly SSH from Cygwin did not.

Uninstalled BlackIce, SSH worked. Reinstalled BlackIce and still working so must have been something with the BlackIce installation.

noel_g
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    I think in BlackIce, you have to whitelist by applications, not by network port. It doesn't quite work like iptables on Linux. – cjc Apr 10 '12 at 17:20
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Look to perfmon counters for network related errors and resends. It may very well be that some portion of your TCP/IP stack is destroying packets on the client.

The impatient-person's replacement for a perfmon analysis is netstat -es on the client machine that is having problems. Compare the numbers from one of the clients that isn't having trouble.

If you want to perform a bit of flailing, reset the TCP/IP stack. Then uninstall and re-install the drivers for your NIC. Make sure you have the latest vendor-supplied bits.

If that fails, try a new network card. Somehow, I sense a subtle physical layer problem in this scenario.

Wesley
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  • I reset TCP/IP Stack and still have the problem. I also tried to do SSH using Putty and that worked. So this does seem to be related to Cygwin and not Hardware. – noel_g Apr 09 '12 at 22:22
  • @noel_g what version of Cygwin are you using? – Wesley Apr 09 '12 at 22:27
  • cygcheck -V shows 1.7.11 – noel_g Apr 09 '12 at 22:36
  • @noel_g Latest version is 1.7.13-1 - not sure if that would help things. Grasping at straws now. – Wesley Apr 09 '12 at 22:37
  • FYI, I noticed that on Putty I was asked to accept certificate from the server and I was asked the same thing on the other 2 machines where I can SSH from cygwin. This particular box is not asking me to accept the certificate. I looked in /.ssh and ~/.ssh on the client and I don't see where this could be stored. Expected to see it in known_hosts – noel_g Apr 09 '12 at 22:39
  • Tried re-install still 1.7.11 using the setup.exe from the main cygwin site – noel_g Apr 09 '12 at 23:10
  • Is that the same version that's on the other PCs where Cygwin works? – Wesley Apr 09 '12 at 23:14
  • Yes, same version as Windows 7 computer that works – noel_g Apr 10 '12 at 00:00
  • Tried something new today. Logged in to Vista using a different account and started Cygwin. Getting warning about /etc/passwd and /etc/group needing to be rebuilt. mkpasswd -l -d > /etc/passwd gives a permission denied error. Wonder if this may be the cause of my SSH problem – noel_g Apr 10 '12 at 14:56
  • FWIW: Ubuntu 14.04 LTS on VMware Player 7.1, Win7-x64. Connections dropping from both cygwin 1.7.29 and teraterm 4.86 on same Win7 host. Connecting from SLES 10.4 across LAN works. – bvj May 04 '15 at 21:34