IOS Upgrade on Cisco 3750

Unanswered Question
Feb 22nd, 2007


Iam doing an upgrade on cisco 3750 to c3750-ipbasek9-mz.122-25.SED1.bin. I notice some circles during the file transfer. But when i do a MD5 check, it looks fine.


Am i overlooking something? Is there any problem with the file upgrade.

Please advise.



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hoogen_82 Fri, 02/23/2007 - 07:09

There is some intermitent loss in connection to the tftp server while recieving the image.

Do ensure you verify the checksum of the image. Also do a verify bootflash: command on ur switch before reloading.



Do rate if this helps :)

navneet_78 Sun, 02/25/2007 - 21:04

Hi Hoogen,

Thanx for the Reply. I did a Verify \MD5 checksum and the output is the same.

So i hope it got copied properly.



hoogen_82 Sun, 02/25/2007 - 21:17

Sure it did then. Verify the checksum too.



Do rate if i have helped :)

amansoi_5 Sun, 02/25/2007 - 21:32

Dear Navneet,

I had also faced similar problem . Can u try changing TFTP Software?



n-magbade Wed, 09/19/2007 - 08:42

I am facing similar problem. Changing the tftp server did not solve it

Richard Burts Wed, 09/19/2007 - 09:00


The O in the output indicates a problem with a particular packet being transmitted by TFTP. TFTP has logic to retransmit these packets. When the transfer completes if you do a verify on the new image file and it indicates ok then it should be fine.

If you are getting lots of errors like this it could indicate that there are poor quality or other problems on one of the links that you go through. If you are concerned about the validity of the image file after transfer perhaps you might consider using FTP to make the transfer rather than TFTP. Since FTP uses TCP which is a reliable transport (and TFTP uses UDP) there might be some advantage for TCP in environments with high error rate on some link.



n-magbade Wed, 09/19/2007 - 09:06

Thanks Rick. I thought it might be a link issue but same symptons when directly connected to the switch.


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