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Cisco 2600 router will not boot

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by lorrainer 1 view

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I have a Cisco 2620 router for which I lost the password. I started following the instructions from Cisco for reseting the password via the console port and ROMMON. I used a notebook computer and hyper terminal. All looked good, until I entered what should have been "confreg 0x2142" at the rommon 1> prompt and then typed "reset". I think I put "confreg 0x2124" instead (duh). Now the router will not boot up (I get a bunch of strange characters on the hyper terminal screen, and I can't get any meaningful response from the router.
Is there some way to force the router to boot from a normal configuration instead of whatever it is trying to do???
Thanks!!

13 replies

by cg it

I know this doesn't quite answer your question, however to communicate with a router that doesn't respond you must interrupt the boot sequence with the CTL+Break command. From there, repairing what happened you might try the command BFE for manual emergency modes, reload which halts whatever is happening and does a cold reboot or try the rlogin command to do a rlogoin connection.

but if you did a write command to erase and rewrite and set a running config which messed up you probably have to reload the IOS.

the other thing to remember, unless you use the exit command to exit out even if you close the hyperterminal connection , the router is still assuming a connection is active until the default console timeout time expires.

by cg it

the gibberish you see might not be gibberish, only that the current session is still in progress.

close out the hyperterminal connection turn off the router, then turn it back on for a cold start boot and see what happens.

[hope your have a failover route for whatever segment this router services].

by lorrainer

Great ideas, but none of them work. Ctrl+Break has very little effect; the garbage stops, but the router remains unresponsive. I also tried a tip for switching to 1200 baud and holding down the space bar while turning the router on. This didn't work either.
Configmaker can't help because the router doesn't respond.
All the other solutions I have seen contain something about "use ROMmon to" do something; if the stupid thing would go into ROMmon, I wouldn't have this problem in the first place...

by cg it

did you try ConfigMaker? see ConfigMaker communicates with the router, learns it IOS settings, allows you to download a saved image on a TFTP server or download an image like a IOS on the CD using the SMTP private RW community string and configures the router for you. It will look a VRam and memory and tell you if you've got a way serious problem.

if you didn't try it get it and try it.

The CTL+Break interrupts the boot sequence so you wont see anything on the screen nor will the router be responsive cuz, no IOS is loaded. redo your password recovery confreg command with the correct string or erase the VRam but I'm betting on ConfigMaker will be able to right some wrongs if you haven't tried it yet.

by cg it

lol you use the CTL+Break or Break at boot up to get into Rommon. is there any prompt showing after you use the CTL+Break or Break??? if you get rommon #> prompt type in configuration-register 0x0 then type reload as long as the configuration register is at 0x0 the router will always boot to rommon... you have to put in the correct configuration register

by lorrainer

I tried ConfigMaker. It is unable to communicate with the router in any way, so is of no use.
There is no prompt of any kind with or without the CTL+Break (I am assuming that by this you mean to hold down the "ctrl" key and press the "break" key; I have never seen this combination referred to as "CTL+Break", only as "Ctrl+Break", so I want to make sure we are talking about the same thing).
When I do press Ctrl+Break, it prints a "C" on my hyper terminal screen. If I try to type in the confreg command and string, it does some interesting characters (like "????C??C??CſC??b??⌡⌡⌡⌡"), but still does the same thing when I reboot it.
No matter what I do, I don't get a ROMmon promt, or any other kind of prompt of any kind.
I don't care if I lose all the configuration info that was in this router; it is no longer in a production environment and needs to be reconfigured anyway; doesn't Cisco build in some way to force the thing back to a basic, default configuration of some kind?
Thanks for your help!!!

by cg it

nope you send a Ctrl+Break message to the router to interrupt the boot process.

yes there is a way to reset it but you have to be in priviledged exec mode and the only to get to that is to have a command prompt.

your problem is the config register should be 0x2102 the 0x2142 is for telling the router to ignor the startup file on next reload. have no clue what typing in 0x2124 would do you heck.....

the standard Ctrl+Break and the link I sent you on how to send a Ctrl+Break when you can communicate with the router via a keyboard is to set your hyperterminal setting to no flowcontrol 1200 baud 8 bit . setting the hyperterminal this way send a simulated Ctrl+Break to the router to interrupt the booting sequence hense interrupting the crapped out IOS thats in there so you can set some command to the router. Cisco has a ton of papers available on troubleshooting their routers but this assumes you have access to them in some way I know Ciscoworks and ConfigMaker all can communicate with a router in some manner unless its a hardware related problem like a dead router or no memory router. CiscoWorks and ConfigMaker all communicate with the router either through the com port, aux port, Telnet or network connection.
A CCIE or CCNP with a couple of years field work might know of some nifty tricks. I only know the hyperterminal Ctrl+Break emulation to interrupt the booting so one can get in there and either reload, download or upload/download stuff to or from NVRam or system memory or write commands to correct problems.
why reject suggestions?? I see people here reject suggestion cuz it's not the exact answer .....foolish.....this isn't an exam cram others see rejected suggestions all the time they don't put their input into questions cuz for the most part, there are others out there who just for kicks think up unanswerable questions just to jerk peoples chains. there are many questions here that go unanswered because of that.

by lorrainer

I'm sorry, but with the only two choice for rating an answer being "Acceptable - Helped me" and "Unacceptable - Didn't help me", so far the latter is where I am. The router is still not communicative, so I am back where I started.

Hopefully someone will know how to start the router from scratch so I can get it to talk to me.

Thanks for trying to help!

by mshavrov

It's not so scarry as it looks. You just changed some fields in the config register which determine consle speed. This is what you have now with the value 0x2124:

* NVRAM Config used
* Boot from the Flash
* Consile speed 19200

So, just change your terminal speed to 19200 and you will see an output. Then follow the instructions on the Cisco website how to "recover lost password".

If you have more questions, just e-mail me directly. Good luck,

Michael Shavrov
CCNP, CCDP, CCSP, CCIE Written, MCSE W2K, MCSE+I, ...

by lorrainer

You Win!! That did the trick.

Thanks so much; now I can actually do something with that router besides hold down papers on my desk...

by cg it

there ya go and it took a CCIE along with all the other Cisco certs to know that that register setting is for the console speed.

have to write this answer down. its a keeper

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