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johnfds
Jun 26, 2007, 12:48 PM
I have an older 3620 that the IOS has been wiped. Rommon displays "command not found" to tftpdnld so I assume it is older that the tftpdnld command. I tried a serial download of a very basic image captured from a working 3640 however upon boot the 3640 displayed "device does not contain a valid magic number" "cannot open flash" "cannot determine first file name on device "flash:" ".

The original ios version was 11.1(20)AA2 I believe.

Any thoughts on the above error messages or maybe how to upgrade rommon so I can try tftpdnld?

Thanks,
John

cajalat
Jun 26, 2007, 12:54 PM
You need to setup a tftp server and place a valid image for download. Then in rommon mode you can set the IP,Mask,GW,tftp server, image path and boot. This will download the image from the tftp server and boot from that image. After that you need to copy the image to the flash and set your bootldr pointer to the new image in flash. I would format the flash first in case there was any kind of corruption before you copy the image to it.

I assume you know a bit about these routers since you own one but if you need detailed instructions let me know and I can provide that for you.

Casey

johnfds
Jun 26, 2007, 01:04 PM
I have an older 3620 that the IOS has been wiped. Rommon displays "command not found" to tftpdnld so I assume it is older that the tftpdnld command. I tried a serial download of a very basic image captured from a working 3640 however upon boot the 3640 displayed "device does not contain a valid magic number" "cannot open flash" "cannot determine first file name on device "flash:" ".

The original ios version was 11.1(20)AA2 I believe.

Any thoughts on the above error messages or maybe how to upgrade rommon so I can try tftpdnld?

Thanks,
John
The process you describe references a TFTPDNLD command which this router apparently does not support.

johnfds
Jun 26, 2007, 01:16 PM
The process you describe references a TFTPDNLD command which this router apparently does not support. Please see original posting.

cajalat
Jun 26, 2007, 05:28 PM
I think your best bet is to download a valid image using xmodem from the console. Here's how you do that:

- At the rommon mode issue a confreg without any options
- Take all the defaults except for the console baud rate and boot options.
-- Change it to the highest from the available options
-- Change your boot option to boot straight from ROM (option 0)
- issue a reset and don't forget to change your hyperterminal to match the same baud rate you choose.
- Issue the xmodem command to download the image from your PC

rommon 1 > xmodem -c imagefor3620.bin

- You'll get a warning which tells you that your flash will be erase. Accept it
- Now you're ready to send the image from your Hyperterminal
- Go to Hypertermin and click TRANSFER menu
- Select SEND FILE
- Follow the dialog box to your image where-ever you saved that on your PC
- Make sure to choose Xmodem in the Protocol drop-down box
- Click SEND

This will take a while but when its down the router will reload itself with the new image. After it reloads you'll need to reset the config register back to 0x2102 so that it can boot the good image going forward instead of going to ROMMON.

thekudzies
Aug 17, 2012, 06:18 AM
Can you elaborate more on the configuartion?step by step from the confreg command