IOS: Reverse SSH Console Access - Part 2
25 June, 2008 by Greg Ferro
Following my original post about configuring Reverse SSH on a Cisco console server, I wanted to make some followup to extend the usage.
Accessing the line port using SSH only.
The advantage to this option is that you need only allow TCP 22 (SSH) through your firewall.
From a *nix platform, you use the following command line:
ssh gf:39@10.216.4.10
When using putty in interactive mode, at the username prompt just put username:number at the prompt.
Putty Profile
If you configure putty profiles (which I use to run putty from the command line).
Connecting from the IOS prompt on your terminal server
Accessing a port on your terminal server using the IOS command line, where 40 is the line number of the serial port that you want connect to.
lontrm01#ssh -l gf:40 10.216.4.10
{Thanks to Emanuele who posted a comment on the original post}
HELP: How do you enter Break Characters to enter ROMMON ?
I have not been able to successfully enter a break character / sequence to break into the boot sequence when using Reverse SSH. From my research, it seems that the break characters when using SSH are different from those using telnet.
I am sure that there is an answer - please leave a comment if you have any tips.
Hi Greg,
I think there is no standard key. On openssh using ~B you ask to remote server to send a BREAK to remote server. But I’m not sure SSHv2 on cisco implement this. I’ve nothing connected to the only reverse SSH box I have, so I can’t test..
And I see no telnet break-on-ip or ip-on-break for ssh.. :-/
Greg Ferro reply on June 26th, 2008 6:44 pm:
I tried ~B on OSX Terminal but it didn’t work. I also activated the ‘telnet -on-break’ but it didn’t work either. The only way I got it to work was to remove the line from the rotary group, telnet (not SSH) as normal, connect a windows keyboard, and open a windows terminal emulator in Parallels. Which isn’t really very good.
[...] published a follow up to this post at http://etherealmind.com/2008/06/25/cisco-ios-reverse-ssh-terminal-server-console-access-part2/ Filed Under: CiscoTagged: Design, [...]