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When I attempt to login via ssh like so ssh marc_mtpt0@m3pt0.com I get this response:

/etc/ssh_config: line 51: Bad configuration option: UseDNS 
/etc/ssh_config: terminating, 1 bad configuration options lost connection

I've done this plenty in the past but it's no longer working properly. Not sure where to go from here or how to fix it. Any help is greatly appreciated. Thanks!

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As the message says, UseDNS is not a valid option name in /etc/ssh_config. There is a server option called UseDNS; presumably you meant to put this line in /etc/sshd_config and edited the wrong file.

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I actually have no idea how that line got into the ssh_config file at all because I've never edited these files before. Slightly confused at how it got in there. But it's all good now. Thanks so much! – Marc Dec 30 '11 at 22:01
@Marc I recommend putting /etc under version control. I use etckeeper wherever it's available. – Gilles Dec 30 '11 at 22:21

Commenting out line 51 in the ssh_config file worked.

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