UNUSUAL PROMPT

mitra.kama · ‎01-16-2010

hi,

I am phasing a problem in RAS cisco 2500, when its boot up , it stops at "Rourter(boot)>" prompt whereas in others it stops at "Router>"

what would be the reason and whether it could be resolved or not ,if yes then how..

tks...mitra..

Giuseppe Larosa · ‎01-16-2010

Hello Mitra,

when router is stucked at router(boot)> it has not been able to execute the main IOS image that is in flash an it is running the bootloader image.

If I understand what is happening you say that some times the router reloads correctly and some other times it is stucked at router(boot)>.

You should connect a console cable to the router to see what happens during bootstrap.

It is probable that the flash is partially corrupted or is going to be.

It may be wise to format the flash and to write again the IOS image on the flash.

Caution: being the C2500 out of support from long time it may be difficult to find an IOS image for it.

So verify that you have a suitable image on your servers or also attempt to upload the IOS image using

copy flash tftp after you get the full IOS image to run.

in boot mode the device is not capable to route packets or to talk routing protocols you can probably use the command above with a TFTP server that is in the same IP subnet as eth0 of C2500.

Hope to help

Giuseppe

Peter Paluch · ‎01-16-2010

Hello Mitra,

The prompt tells you that the router has not booted using the IOS from the FLASH but only a small backup IOS from the router's ROM. This mode is called the BootROM mode. A 2500 series router boots into the BootROM mode either if the IOS in the FLASH is erased or corrupted, or if the configuration register value is changed so that it directs the router to go into the BootROM.

Try to enter the command show flash to see if the proper IOS is stored in the FLASH. Also verify using the command show version that the configuration register value is set to 0x2102. If the IOS is missing from the FLASH you will need to download it there (you will need a PC running a TFTP server software for that, and obviously, the IOS itself). If the configuration register value is different from 0x2102 you will have to correct it by entering the command config-register 0x2102 in the global configuration mode. Do not save the configuration after you change the configuration register value - the change is applied immediately, and saving the configuration may in fact store a corrupted version, as the IOS in the ROM does not recognize all commands for a full IOS version, and is not able to write them in a new configuration file.

Also, using the show startup-config, try to check if there are any commands of the boot system form in the configuration file. If they are misspelled they may again cause the router to fail booting the full IOS. In such a case, set the configuration register to the value 0x2142, reload the router (it will boot into the full IOS but will ignore the stored configuration). Then use the command copy startup-config running-config to activate the stored configuration. In the global configuration mode, remove the boot system commands and return the configuration register value back to 0x2102. Then you may store the configuration using the command write and reload the router. You may also need to correct other parts of the configuration (such as activating the interfaces, as they will remain in a shutdown state).

Best regards,

Peter

mitra.kama · ‎01-20-2010

tks for nice guidance..

I tried your suggestions but i found that while running sh flash we get:

1. 5710180 c2500-i-l.120-7 [invalid-checksum]

router(boot)#

I am unable to copy ios form ftp because there is no option of ftp while coping form ftp to flash,only tftp is available, whereas ftp was available while coping from flash to ftp.

I had copied flash in ftp.

Now , why invalid-checksum is showing , is it making any difference, i mean to say that is ios is corrupt or flash is unserviceable.

tks..

Peter Paluch · ‎01-20-2010

Mitra,

Both options are possible - that either the image or the FLASH itself is corrupted.

Yes, the BootROM IOS image does not support the FTP protocol. The only option is to use TFTP. If you are running Linux on your workstation I can heartily recommend the atftpd software - a very good TFTP server implementation. You can install it using your favourite package manager. If you are running Windows then perhaps the Kiwi TFTP server from the Kiwi CatTools package will do for you. You can download the software here:

http://www.kiwisyslog.com/kiwi-cattools-download/

Best regards,

Peter

mitra.kama · ‎02-06-2010

thanks for guidance

my problem has been resolved.. tks..

Mitra..