Bypass unknown Cisco password.

[jasonb]

Thanks to Glen Campbell

Q:
I had a technical question regarding cisco equipment. I have a router{2610} that a former isp left and has never picked up and I would like to play with it. However I don't know the username or password. Do you know if there is a default username and password? There appears to be a reset jumper on the motherboard and I was wondering if I did a hardware reset it might start using a default username and password if there is such a thing. I havn't seen anything on cisco as yet do you know of anything? I've found an article on reseting the password but it says you still need to do a show version first to determine the memory address of the password. You can't do lka show version with out getting past the username.

Any ideas? I hate having some nice equipment sitting around collecting dust.

A:
What is likely your best bet is to first try 'cisco' and 'cisco' for the user and enable passwords. If that doesn't work, the note you saw is likely talking about what's known as the config reg - the Configuration Register. Yes you can do a 'sh ver' in usermode. That will tell you the current config reg. It's likely to be 0x2102. What it tells you is where the router begins to read it's config. When you change that value, you can boot the router as if it has never been configured before. You do that by plugging into the console port, set you comm to 9600 N81, and send a couple of Break's as the router boots (ie. turn it off and on). That should put you into rommon mode. If you do a ? at the rommon> prompt, you can see how to change the config reg. Set it to 0x2142. Reboot it. The router should then pop into setup mode - as if there were no setup config. Enter whatever you want - you really just want to get to the # prompt. Once that's done, you can do a 'sh startup-config' - to see the config the router normally boots up with. If you want to save that config, have your terminal app save the buffer to a text file just before you run 'sh startup-config'. Once you have the old config, and you feel you've configured it the way you'd like you can copy the running config to the startup config - just like that, too: 'copy running-config startup-config'. The router will then boot with your configuration, having overwritten the old startup-config. Reboot the router, go back into rommon> mode with the Break key again, change the config-reg back, and reboot again. You'll be
looking at your config.