Problem in copying ios to tftp server

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Jan 22nd, 2008
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Hi frndz,

I was taking backup of IOS of all the network devices.But i noticed one thing that after few excalamation there were dots as shown below and in the attachment:-


Although i verified that both the flash and the copyied file to tftp server were of same size.

Is the IOS copyied correclty ? Any another method to verify the same?

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Overall Rating: 5 (1 ratings)
Danilo Dy Tue, 01/22/2008 - 06:47
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You need the MD5 Signature of the IOS. If you don't have it from the download site, you can run the following in the router.

Router# verify flash:ios_file_name.bin

Copy the "CCO Hash MD5" Signature to a Notepad

Download an MD5 checker from internet and use it to check the IOS uploaded in your TFTP server. Copy the MD5 Signature to a Notepad

Compare the MD5 Signature from the router and your PC.



Richard Burts Tue, 01/22/2008 - 08:35
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Dandy gives good advice about how to verify that the copied IOS is ok. I would like to supplement his comments with a comment about TFTP. The dots that you see during the transfer indicate that 1 (or more) packets were dropped during transmission. TFTP has a mechanism to recognize when dropped packets occur and to retransmit the missing packets. If the TFTP copy ran to the end and did not generate any error messages, then it is likely that the copy was ok and that the IOS file on the server is valid.

Following the advice given by Dandy will allow you to be very sure. But the presence of some dots during the TFTP transfer is not necessarily a reason to suspect that you wound up with a corrupt IOS.



amolwaghmare Wed, 01/23/2008 - 23:24
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Thanks guys it was very useful especially Dandy suggestion :- 5 points for him


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