Recover IOS from Rommon

Ok so i made the mistake of completely wiping my flash....or maybe i just did it cause subconsciously wanted to practice

Connected via console and i have the router (831) connect via one of the lan ports to the tftp server, not sure if this is the way to do it.

Anyway here is the output i get and the error that follows after i type "tftpdnld":

System Bootstrap, Version 12.2(8r)YN, RELEASE SOFTWARE (fc1)
TAC Support: http://www.cisco.com/tac
Copyright (c) 2002 by cisco Systems, Inc.
C800/SOHO series (Board ID: 29-129) platform with 49152 Kbytes of main memory

boot: cannot determine first file name on device "flash:"

System Bootstrap, Version 12.2(8r)YN, RELEASE SOFTWARE (fc1)
TAC Support: http://www.cisco.com/tac
Copyright (c) 2002 by cisco Systems, Inc.
C800/SOHO series (Board ID: 29-129) platform with 49152 Kbytes of main memory

rommon 1 > set
PS1=rommon ! >
BSI=0
RET_2_RUTC=0
RET_2_RTS=
SUBNET_MASK=255.255.255.0
DEFAULT_GATEWAY=10.10.10.1
TFTP_SERVER=10.10.10.5
TFTP_FILE=c831-k9o3sy6-mz.123-11.YZ1
IP_ADDRESS=10.10.10.2
0=4
TFTP_VERBOSE=1
?=1
rommon 2 > tftpdnld

IP_ADDRESS: 10.10.10.2
Missing or illegal ip address for variable IP_SUBNET_MASK
Illegal subnet mask.

Looked through some of the threads here and the cisco documentation but im beating my head against a wall at this point.

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Comments

Delirious

Never mind i figured it out.

Subnet mask needs to be set with IP_SUBNET_MASK and not SUBNET_MASK. Not sure why it would accept the subnet_mask command if thats not correct.

malcybood

Hey,

Not sure if you know this or not but you can also do this by using a feature called xmodem via console cable.

Check out the section at this link Installing the Router Software by Using the Console

http://www.cisco.com/en/US/products/sw/iosswrel/ps1830/prod_release_note09186a0080081174.html

Malc

Delirious

malcybood wrote:

Hey,

Not sure if you know this or not but you can also do this by using a feature called xmodem via console cable.

Check out the section at this link Installing the Router Software by Using the Console

http://www.cisco.com/en/US/products/sw/iosswrel/ps1830/prod_release_note09186a0080081174.html

Malc

Thanks malcybood, I have read of the painful ways of xmodem on here.

I'm able to get the image to the router now but when i reset it i get the message "cannot determine first filename on device."

Then it goes into rommon mode after a couple tries.

I checked the flash useing the dir command and the image is on there but its giving me a "bad checksum error."

So i went back and added the "TFTP_CHECKSUM=0" command and im still getting the same thing.

Any ideas?

Delirious

Well the message says

"cannot determine first filename on device flash:"

When i get into rommon i can do a >dir flash: and it shows the ios file on the flash. So i dont know why it cant read the filename.

I'm at work now so ill have to mess with it more when i get home.

malcybood

can you copy and paste the whole output?

markzab

Welcome to my world...

http://techexams.net/forums/viewtopic.php?t=23248

Have fun. Just leave a tip for Darby on your way out.

Delirious

I'll put up the whole output when i get home from work.

markzab wrote:

Welcome to my world...

http://techexams.net/forums/viewtopic.php?t=23248

Have fun. Just leave a tip for Darby on your way out.

wow! I hope the 2924 and the 2950 i got off ebay dont have problems like that. Im in the right place for help though, and im sure it would be a good learning experience.

markzab

Delirious wrote:

I'll put up the whole output when i get home from work.

markzab wrote:

Welcome to my world...

http://techexams.net/forums/viewtopic.php?t=23248

Have fun. Just leave a tip for Darby on your way out.

wow! I hope the 2924 and the 2950 i got off ebay dont have problems like that. Im in the right place for help though, and im sure it would be a good learning experience.

I learned a hel of a lot going through those 5-7 hours in that thread. It was my first and 2nd time using xmodem all in one night. I posted it just in case you have to do the same thing to your machine. Have fun.

Delirious

Ok, heres what i get when it boots up after using tftp

System Bootstrap, Version 12.2(8r)YN, RELEASE SOFTWARE (fc1)
TAC Support: http://www.cisco.com/tac
Copyright (c) 2002 by cisco Systems, Inc.
C800/SOHO series (Board ID: 29-129) platform with 49152 Kbytes of main memory

boot: cannot determine first file name on device "flash:"
System Bootstrap, Version 12.2(8r)YN, RELEASE SOFTWARE (fc1)
TAC Support: http://www.cisco.com/tac
Copyright (c) 2002 by cisco Systems, Inc.
C800/SOHO series (Board ID: 29-129) platform with 49152 Kbytes of main memory

boot: cannot determine first file name on device "flash:"

System Bootstrap, Version 12.2(8r)YN, RELEASE SOFTWARE (fc1)
TAC Support: http://www.cisco.com/tac
Copyright (c) 2002 by cisco Systems, Inc.
C800/SOHO series (Board ID: 29-129) platform with 49152 Kbytes of main memory

rommon 1 >

And heres what i get when i check the flash

rommon 1 > dir flash:
File size Checksum File name
8646068 bytes (0x83edb4) 0x6f35 c831-k9o3sy6-mz.123-11.YZ1.bin (bad chec
ksum: 0x9e60)
rommon 2 >

iproute

Delirious wrote:

Ok, heres what i get when it boots up after using tftp

System Bootstrap, Version 12.2(8r)YN, RELEASE SOFTWARE (fc1)
TAC Support: http://www.cisco.com/tac
Copyright (c) 2002 by cisco Systems, Inc.
C800/SOHO series (Board ID: 29-129) platform with 49152 Kbytes of main memory

boot: cannot determine first file name on device "flash:"
System Bootstrap, Version 12.2(8r)YN, RELEASE SOFTWARE (fc1)
TAC Support: http://www.cisco.com/tac
Copyright (c) 2002 by cisco Systems, Inc.
C800/SOHO series (Board ID: 29-129) platform with 49152 Kbytes of main memory

boot: cannot determine first file name on device "flash:"

System Bootstrap, Version 12.2(8r)YN, RELEASE SOFTWARE (fc1)
TAC Support: http://www.cisco.com/tac
Copyright (c) 2002 by cisco Systems, Inc.
C800/SOHO series (Board ID: 29-129) platform with 49152 Kbytes of main memory

rommon 1 >

And heres what i get when i check the flash

rommon 1 > dir flash:
File size Checksum File name
8646068 bytes (0x83edb4) 0x6f35 c831-k9o3sy6-mz.123-11.YZ1.bin (bad chec
ksum: 0x9e60)
rommon 2 >

Have you tried:
- Erase the flash and re-copy the IOS
- Try a different IOS
- At the rommon prompt: boot flash:ios_file_name

Delirious

DarbyWeaver wrote:

Seems like you may need to run the command:

squeeze flash:

on the 831 but I forget - I've been doing 871's lately as VPN Routers.

Seems like i remember reading that some where too, i just assumed that since the ios was small enough fit on the flash i wouldn't need to. Assumption seems to be the mother of evil for me

I'll give that shot though.

Delirious

Ok shes up and running now.

I had to load the new image into ram, go in and erase the flash again, and then run squeeze. From there i was able to copy the image over to flash.

Thanks for the help everyone!