SSH cipher mismatch!?

Ok, so recently we updated some of our Linux systems, some we have not. When I tried to SSH into an older system from a newer system I received an error:

“Unable to negotiate with port 22: no matching cipher found. Their offer: 3des-cbc” ?!

I’ve seen similar errors before, didn’t make good notes on how it was resolved.. so here are a couple of items.

1 – nano ~/.ssh/config and set the connection parameters for each server you often connect to using the example below: – there are other items you can provide but this is all I needed to login!

Host myserver
	Hostname my-linux-host.local
	User angeln
	Port 22
	Ciphers 3des-cbc

There are other things you can do, like add ciphers to the server – but I don’t cover that here. If elect to try it, i’ll post some details here in the future. Google It!?

FYI – a new useful tool, you can use verbose mode to see the ciphers the client is trying and the server is responding too … ssh -vvv angeln@

     -v      Verbose mode.  Causes ssh to print debugging messages about
             its progress.  This is helpful in debugging connection,
             authentication, and configuration problems.  Multiple -v
             options increase the verbosity.  The maximum is 3