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Community Member

Cisco 857: Bad block number

My router was unable to boot normally and none of the LEDs were on after 15 seconds of booting it. So I connected to it using PuTTY and here is the output:

System Bootstrap, Version 12.3(8r)YI4, RELEASE SOFTWARE

Technical Support:

Copyright (c) 2006 by cisco Systems, Inc.

C850 series (Board ID: 2-149) platform with 65536 Kbytes of main memory

flashfs[0]: Checking block 62...bad block number (-1)

flashfs[0]: erasing block 62...

How long is this erasing supposed to take? The process seems frozen to me. Is there anything I can do at this stage? Configuring the router has been a nightmare from the start, I am way out of my league here so please help.


Re: Cisco 857: Bad block number

This is because your old flash had an IOS image in it, and your new flash didn't have an image? It might be happened due to the Ethernet 10BASE-T cable is unplugged.

Community Member

Re: Cisco 857: Bad block number

This information doesn't really help me solve the problem of getting the device back online.

Community Member

Re: Cisco 857: Bad block number

I don't remember if the 851 has an external flash disk, if it does not you will need to either TFTP_DNLD (if supported) or X-Modem to get a working image on the device and bring it back online.

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