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New Member

Need some advice on flash file system.

I am not sure if this is the right forum to raise this problem.

I Need some advice on flash file system.

Consider a situation where there are 3 files in flash Two files in flash are with same name (say xyz.bin) and the third is having a different name (say abc.bin). The router has booted from abc.bin. Out of the other two files one is having an invalid checksum. Also in sh flash command, the file with invalid checksum is having the 2nd entry and 3rd entry is the file with correct checksum. What will happen if the entry in boot system IOS command is changed to xyz.bin. i.e :

boot system flash:xyz.bin ?

The file abc.bin is c3640-is-mz.122-5a.bin

and xyz.bin is c3640-is-mz.120-7.T.bin

the output of sh flash :

System flash directory:

File Length Name/status

1 10874164 c3640-is-mz.122-5a.bin

2 1409024 c3640-is-mz.120-7.T.bin [invalid checksum] 3 8141044 c3640-is-mz.120-7.T.bin [20424424 bytes used,

13130008 available, 33554432 total] 32768K bytes of

processor board System flash (Read/Write)

Will the router boot normally? Thanks in advance.......javed

New Member

Re: Need some advice on flash file system.

I would say. If the router cannot boot from xyz.bin when it tries by default to boot from the first valid file in flash. Then by forcing it to boot from xyz.bin it would fail.

Give it a go


Barry Hart

New Member

Re: Need some advice on flash file system.

Dear Barry,

there are two image files in the is the image with invalid checksum.I couldn't delete this invalid image.because once I try to delete it,it says there is no image with this name.When reloading the image again,I see the new image twice,the valid checksum and the invalid checksum.When I try to boot from the new image,it couldn^t not find.

how can I delete this image with invalid checksum?

Tahsin Bekdemir


New Member

Re: Need some advice on flash file system.

There is an other way to get around this problem. Copy your good bin's to a tftp server. Then delete flash. Then copy back your good files.

To come back to your first question. Your box will boot the first file in flash. If you specify boot system flash, it will do an attempt to boot that image. If it fails, it moves back to the default as I described earlier.


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