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One of my Cisco routers died over the weekend, Cisco sent the replacement and I restored the the config using copy tftp: running-config. Everything seems to work fine but I can no longer ssh into the router (I can telnet). The connection is refused, so it isn't listening on port 22 it seems like.

I had previously backed up the config by just doing ssh router 'show run' > backup_config from my workstation.


  1. Is there anything wrong with my method of backup vs copy running-config tftp:?
  2. I know I haven't given any debug information, but is there something typical I need to do to get ssh working?
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up vote 6 down vote accepted

I believe that your crypto keys may not have been backed up, running something like

router(config)# crypto key generate rsa

will enable ssh.

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It will prompt you for the key length. I suggest 1024 so you can support SSH v2. – Peter Feb 16 '10 at 15:24
Will this effect any IPSec site to site tunnels? (The one active one I have is currently up) – Kyle Brandt Feb 16 '10 at 15:25
I don't think so, but... – mat Feb 16 '10 at 15:46
Okay thanks mat, going to have to wait for a maintenance window to accept the answer :-P – Kyle Brandt Feb 16 '10 at 18:06

Does transport input ssh show under line vty 0 4?

It seems unlikely but there could be a really old IOS on there that doesn't support SSH.

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