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So I can't SSH outside the corporate firewall to my personal development environment. It's a Windows shop. I use Cygwin and bash so I can actually get work done. SSH doesn't work.

I installed corkscrew with Cygwin. I have the following in my ~/.ssh/config:

ProxyCommand corkscrew _proxy_ _port_ %h %p

Executing this at bash:

ssh _user_@_host_._tld_

Gets me:

ssh: Could not resolve hostname _host_._tld_: hostname nor servname provided, or not known

OK, so I try to debug it:

ssh -vvv _user_@_host_._tld_

Which nets me an extra:

debug2: ssh_connect: needpriv 0

That's as far as I can get.

I understand that there's a lot of variables at play. I just need a pointer in the right direction. What is ssh trying to use as a DNS server? Where would I set that in a Cygwin install? How does Internet Explorer resolve hostnames outside the corporate LAN?

I would like to use Cygwin without PuTTY for simplicity, but if there's no way, I'll use PuTTY.

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I made a quick test under Linux and didn't find any DNS request made by ssh on the target host. The next -vvv line after the one you posted is debug1: Executing proxy command: …. It may help if you post the whole ssh -vvv trace and your whole ~/.ssh/config, obscuring only the minimum necessary for privacy. – Gilles Sep 29 '10 at 21:33
Does _host_ look somewhat like an IP address (e.g. beginning with a letter)? In case it matters, I suggest you obscure host names by replacing each letter by z and each digit by 9 (and leave any - and . unchanged). – Gilles Sep 29 '10 at 21:36
So today, after a reboot, I'm getting a totally different debug trace. I didn't get a <code>debug1: Executing proxy command: ...</code> yesterday. Maybe it's because I changed my ~/.ssh/config and needed to restart some process or another. I did kill my Cygwin bash session yesterday, but that didn't do it. Now I'm getting complaints about my crytographic key files (that I used ssh-user-config to generate, BTW...). But that's a totally different question. – alyssackwan Sep 30 '10 at 16:08
up vote 0 down vote accepted

So, for me, a reboot got around this DNS issue. If you've changed your ~/.ssh/config file, and it's not working, try rebooting, at least under Cygwin.

I'm still getting complaints about my cryptographic keys, but that's a totally different question. :)

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