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From: Theo <theom+news@chiark.greenend.org.uk>
Newsgroups: comp.sys.raspberry-pi
Subject: Re: How to boot from SD but run from USB?
Date: 24 Jan 2025 09:10:19 +0000 (GMT)
Organization: University of Cambridge, England
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Originator: theom@chiark.greenend.org.uk ([93.93.131.173])

Chris Green <cl@isbd.net> wrote:
> A script to update the bootcode.bin on the FAT drive should be pretty
> simple, just put it in /etc/rc.local and it will be run every time you
> boot.  It won't matter running it if /boot/bootcode.bin hasn't been
> updated, though I suppose you might complain that it's writing to the
> SD card unnecessarily.  OK, use rsync and the file will only be
> written if it has changed.

I'd probably want to do that after any package updates, because there's a
risk that the firmware files on the SD and USB become out of sync and that
could cause a boot failure.

If you ran it on a cron job say once a day using rsync, it would reduce the
chances of that happening.  Or there may be a hook you can set to run it
after apt upgrade.

Theo