03-23-2009 04:08 AM - edited 03-04-2019 04:02 AM
Hi All,
I'm trying to enter Rommon mode on a Cisco 870 series Router. This is to recover a corrupt IOS image.
Basically when I send Break during boot, it just cycles the System Bootstrap instead of entering Rommon mode.
I am using TeraTerm and sending Alt + B. I've also tried with HyperTerminal and sent CTL + B, but get the same outcome.
Does anybody know if the procedure is different on 800 series routers? It doesn't appear so from looking at other bits of info.
See below for the output whilst booting:
System Bootstrap, Version 12.3(8r)YI4, RELEASE SOFTWARE
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 2006 by cisco Systems, Inc.
C870 series (Board ID: 1-148) platform with 131072 Kbytes of main memory
Booting flash:/c870-advsecurityk9-mz.124-15.XY3.bin
'Here is where I sent the Break, which causes Bootstrap reload'
System Bootstrap, Version 12.3(8r)YI4, RELEASE SOFTWARE
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 2006 by cisco Systems, Inc.
C870 series (Board ID: 1-148) platform with 131072 Kbytes of main memory
Booting flash:/c870-advsecurityk9-mz.124-15.XY3.bin
Error : compressed image checksum is incorrect 0x4DCCADCB
Expected a checksum of 0x8F526C45
*** System received a Software forced crash ***
signal= 0x17, code= 0x5, context= 0x0
PC = 0x0, Vector = 0x0, SP = 0x0
TIA
Kevin
03-23-2009 11:20 AM
Hi Kevin,
Just send a break (ctrl-break) during the boot sequence.
http://www.cisco.com/en/US/docs/routers/access/800/801/software/configuration/guide/rommon.html
Please let us know how things work out.
Toshi
03-25-2009 08:38 AM
on Teraterm, how do you send a ctrl-Break ?
I only know that Break is sent with Alt D but it doesn't work
03-25-2009 11:24 AM
just press two keys "Ctrl" + "Break"
03-25-2009 12:14 PM
I know the Ctrl Key but the Break key doesnt exist !
On Teraterm, you must press Alt B to send a break
and Ctrl Alt B doesnt work
03-25-2009 12:20 PM
Hi Fremont,
It's me again.
TeraTerm? Please check this link out!
http://www.cisco.com/en/US/products/hw/routers/ps133/products_tech_note09186a0080174a34.shtml
HTH,
Toshi
03-25-2009 12:21 PM
power off
connect a console cable
set speed in terminal - 300
power on
wait 1 minute
change speed in terminal to 9600
you should be in rommon
03-25-2009 08:42 AM
Sorry, I would say Alt B not Alt D
Ctrl Alt B doesnt work
03-25-2009 08:34 AM
I just have the same pb with a Cisco 857
If I send a break (Alt-D with Teraterm), it reboots but when I leave it cooting, I have:
C850 series (Board ID: 2-149) platform with 65536 Kbytes of main memory
Booting flash:/c850-advsecurityk9-mz.124-15.T3.bin
Error : compressed image checksum is incorrect 0x972A2B28
Expected a checksum of 0xC6EA1672
*** System received a Software forced crash ***
signal= 0x17, code= 0x5, context= 0x0
PC = 0x0, Vector = 0x0, SP = 0x0
Don't what to do
03-25-2009 08:43 AM
just change the boot order;
(conf)#config-regiter 0x0
reload
03-25-2009 10:26 AM
I just said that I cannot issue anything
I can't break boot sequence
03-25-2009 12:44 PM
I found my problem in the end.
Cannot remember the exact article on Cisco website but a command had been applied which prohibitied me from entering Rommon. Removing the flash completely erased config, etc which was blocking me in the 1st place.
Powered off the Router, removed the Flash, powered up the Router. Router failed to boot without flash, but I was able to enter rommon mode.
Powered off, reinserted Flash. Powered up, Entered Break during boot and straight into Rommon. I was then able to recover IOS using tftdnld.
Hope this helps you too.
Thanks,
Kevin
03-25-2009 12:45 PM
Kevin,
5P! Good job!
Toshi
03-25-2009 03:31 PM
Hi Kevin,
This will work if your appliance has a removable compact flash. The problem is the 870 router doesn't have this luxury.
03-25-2009 03:32 PM
Hi Kevin,
This will work if your appliance has a removable compact flash. The problem is the 870 router doesn't have this luxury.
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide