TFTP IOS Download

[refram]

The IOS on a 2620 router recently became corrupted. Like a good boy, I save the IOS from my routers onto a TFTP server. I copied the IOS for that router back but when the copy was complete, it said that the checksum was bad. I tried a different IOS that I know has worked elsewhere and it also said it was bad. I changed out the Flash memory and the downloads still say they have a bad checksum. Any other ideas?

[smothuku]

Hi ,

Can you paste the exact error which you are getting after loading ios and what is the mode of router ..is it rommon mode after loading ios .

Thanks,

satish

[refram]

Smothuku,

When I download the file, I get an immediate message that says, "Checksum invalid. Do you want to continue anyway? [yes/no]". That's basically it. When it boots it says that the checksum is bad...expects to see one checksum, but sees another. Do you need the exact numbers? Meanwhile, when it goes beyond the checksum error after a boot, it then goes into ROMMON mode. Also, if I load using tftpdnld -r, I still get a bad checksum warning.

[minumathur]

Hi.

Some time TFTP server also have some problem, so try solarwind tftp server for copying IOS in router.

I was also facing same problem, but in my case , i was change TFTP software, this was solve my problme,

so use different TFTP server software.

-minu

[#5]

I also use the Solarwinds 2003 Standard Edition server. Works fine.

I have a TAC case open currently for a problem similiar to the one you describe, but on a 2621XM-DC. Working with them, we are going to RMA the unit on bad Flash. In my case, I have the bad checksum AND cannot erase the flash when I go to write it.

Good question on rommon vs ios. Interested to know that answer. Mine dies either way. At rommon, tftpdnld -r will load the IOS direct to DRAM and give you some more options at the IOS prompt to check out the problem.

--Ron

[refram]

Smothuku,

When I download the file, I get an immediate message that says, "Checksum invalid. Do you want to continue anyway? [yes/no]". That's basically it. When it boots it says that the checksum is bad...expects to see one checksum, but sees another. Do you need the exact numbers? Meanwhile, when it goes beyond the checksum error after a boot, it then goes into ROMMON mode. Also, if I load using tftpdnld -r, I still get a bad checksum warning.

[smothuku]

Hi ,

Have you tried with same image from cisco site ? Download image from cisco site and try once.Try to load the ios using xmodem procedure.

Thanks,

satish

[kerryrowland]

Have you tried to delete and squeeze the image from ROMMON and then attempt a tftpdnld?

[refram]

Sorry, I haven't heard of this one. The image deleted when the the new one loaded. I don't know how to delete it before the download.

[smothuku]

Hi ,

check the below link for loading ios using tftpdnld.

***** Note: As detailed in Cisco bug ID CSCdk81077 ( registered customers only) , for Cisco 2600 and 1720 Series Routers running the ROM monitor command tftpdnld, the command might report a bad checksum comparison when it loads Cisco IOS software images of Cisco IOS Software Release 12.0(2.2)T or later.

Note: As a workaround to this problem, set the ROM monitor variable TFTP_CHECKSUM to 0. This is done by defining the variable TFTP_CHECKSUM=0 from the ROM monitor set command, and then proceeding with the tftpdnld procedure.

follow the steps mentioned in the document and load the ios.

http://www.cisco.com/warp/public/471/76.html

All the best .... :)

Thanks,

satish

[refram]

I tried it, it didn't help. I also tried the xmodem bit and it kept timing out just as it was getting ready to finish. Please, someone, there has got to be SOMETHING.

[Alan.Temmer]

i had the similar problem once,i entered in rommon,deleteted all flash,and then i downloaded new ios via hyper terminal in windows - xmodem procedure (speed 9600)

everything was ok

only problem is when u type in rommon copy xmodem flash:..bin You need to upload image from hyper terminal within 3 sec (default wait time,cant change it).

easy to do it

if u still have problem send me mail alan@storm.hr

[wim_depauw]

Hi,

Try to format the flash , most likely this is corrupted .

# format flash:

gr

wim