Need help for IOS upgradiation

Unanswered Question
Sep 3rd, 2008


I am planning to upgrade the IOS in 2950 for the same i have verified the flash in my flash showing two IOS. But its booted with one IOS with out boot system command .

How switch will choose the IOS means based on which parameters??

SW#sh flash

Directory of flash:/

2 -rwx 1674921 Apr 30 2001 15:09:51 c2950-c3h2s-mz.120-5.3.WC.1.bin

4 drwx 10176 Jan 01 1970 00:00:19 html

5 -rwx 660 Mar 31 1993 04:34:36 vlan.dat

165 -rwx 284 Jan 01 1970 00:17:26 env_vars

166 -rwx 2774747 Mar 07 2003 20:45:37 c2950-i6q4l2-mz.121-12c.EA1.bin

167 -rwx 4812 May 28 1993 18:32:45 config.text

168 -rwx 47 May 28 1993 18:32:45 private-config.text



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Overall Rating: 5 (1 ratings)
Edison Ortiz Wed, 09/03/2008 - 09:53

Whichever it finds first in the flash:

Per your output, it will boot from c2950-c3h2s-mz.120-5.3.WC.1.bin as its listed first.

Don't let the switch pick from the list and use the boot system flash command in the configuration. Any reason for not doing so?



vaisharm Wed, 09/03/2008 - 10:09

Hi Sateesh

Without a boot statement, by default the switch/router would pick the first file in the flash to boot the device. If the first file is not a valid IOS image bin file, the device would drop into ROMMON or boot mode depending on the platform.



sateeshk10 Wed, 09/03/2008 - 10:14


Thanks for info..

But it took second come??

As per the flash IOs seems to be ok and suppose to take first one...right??



Edison Ortiz Wed, 09/03/2008 - 11:38

Yes, it's supposed to take the first one. Please post the running-config along with the show boot output.



johnnykman Wed, 09/03/2008 - 11:47


On a CCIE blog, there was a similar question for a 3750 switch. I'm sure the same logic applies here. Enter the command show boot on your switch. You should see a BOOT path-list entry. This probably will have both IOS files listed. They had used the "archive download-sw" command to add the new IOS to flash and found that one of the default settings is; The BOOT environment variable is changed to point to the new software image on the flash: file system.


sateeshk10 Wed, 09/03/2008 - 12:11


pls find below the required details..

sh run attached...

SwW#sh boot

BOOT path-list: flash:c2950-i6q4l2-mz.121-12c.EA1.bin

Config file: flash:config.text

Private Config file: flash:private-config.text

Enable Break: no

Manual Boot: no

HELPER path-list:

NVRAM/Config file

buffer size: 32768

Edison Ortiz Wed, 09/03/2008 - 14:54

Your boot statement contains the file so a 'search' in the flash: system isn't made.

BOOT path-list: flash:c2950-i6q4l2-mz.121-12c.EA1.bin

Perhaps it's not showing in the running configuration because the set boot command was used instead of the boot system command.





Please rate helpful posts

arupbiet2006 Thu, 09/04/2008 - 00:42

1st one is help to boot ur router...u can delete the flash and then install new ios in your router


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