Friday, January 23, 2009

Cisco - Loading New IOS

Issue: You need to update the IOS on your Cisco Router or Switch

Quick: copy tftp: flash:
It is very easy to do but you need to have a tftp server running to copy the files. You can run it on a workstation or laptop. Here are some links to download free tftp servers that you can get online:

You just need one of these.
I used the tftpd32 program. Just download the file and run it. Launch the install application from the start menu and see something like this:

Run the copy command as shown to copy the file from the tftp server to the cisco device:

router#copy tftp: flash:
Address or name of remote host []? X.X.X.X --> Ip address where the tftp server is and the file is stored
Source filename []? xxxxxx.bin ----> IOS file name (include the extension)
Destination filename [xxxxx.bin]? Just press Enter
Get prompt to Erase flash before copying? [confirm] Just press Enter to confirm.
That will access the TFTP server and start copying the file on to the flash of the router. You will see the router working on the copy.

Once the file is copied, check with a "show flash" that the file is properly stored.
router#show flash
router#config t
router(config)#boot system flash:xxxxxx.bin -----> the IOS file name.
router#wr mem
confirm? Yes

You will lose your telnet session at this point and it will take several minutes before you can ping and connect to the router again.

After the reload is done, check if the IOS upgrade has been succesfully done, by running a "show version" and check that the new file is loaded.


Anonymous said...

I was really struggling with tftpd32 software to flash Cisco 7961, but was troubled by this 46:46:3a:46:46:3a error.

As soon as I unchecked 'ping before assign IP' per your suggestion, things started working. I really appreciate this forum you have posted.
Thank you

Akash Patel

Jimmy said...

You are welcome, Glad it helped.