How can I boot Cisco1841 with USB Drive instead of CF?

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Oct 3rd, 2010
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I need to boot Cisco1841 with USB Drive instead of Compact Flash but I don't know what should I do.

I heard I need to format USB Drive with FAT and need to save IOS on the USB Drive.

Before boot, Need to set config register ? I am not sure which parameter should I set config register in detail.

Please let me know if there is URL describing thease steps from the beginning.

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paolo bevilacqua Mon, 10/04/2010 - 04:02
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Why you think you need to boot from USB ?

vragotha Tue, 10/05/2010 - 06:25
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     Q. What sizes of USB Flash sticks are supported?
     A. USB Flash sticks are supported in 64, 128, and 256 MB sizes. No other sizes are supported.
     Q. Can I use any USB memory stick for this application?

     A. No. Only Cisco USB memory sticks are supported.
Q. Can I boot an image directly from the USB Flash module?
A. Yes. USB drivers have been added to rommon, starting with version 12.4(13r)
     Q. Can I format the USB Flash module on the router?
A. Yes. You can format the module on either a router or a PC. You must  specify "FAT16 file system" as the file system for the PC format process  to use.
If your setup satisfies above conditions you can get the router to boot up with the IOS on the USB flash
If you are in ROMMON mode, use 'dev' to find out the name of the USB Flash (should be usbflash0).
set BOOT=usbflash0:
If you are in the router,
boot system flash usbflash0:
Leo Laohoo Tue, 10/05/2010 - 15:14
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Because Compact Flash is broken

In addition to Vijay's post (+5), USB size of UP TO 2Gb is supported.

The bad news is that in your case, unless the router Bootstrap/ROMmon is upgraded to 12.13r(T6), then it won't work.  Which is why I'm going to ask you to be specific when you say the CF is "broken".  The CF is broken or the CF SLOT is broken?

If the CF alone is broken, then you can easily fix this by getting a CF (no more than 2Gb in size) and use that instead.  Get a media card reader and format it to FAT16 with a computer and copy the file from your computer to the CF via the media card reader.


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