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<div>On Thu, 30 Apr 2026 00:46:30 +0200 Pascal Hambourg <pascal@plouf.fr.eu.org> wrote:<br>
> Thorsten Behrens wrote:<br>
> > A thought on how to improve the postinst of grub<br>
> > Something along these lines - not this exact script, but in spirit - would update grub on all ESPs<br>
><br>
> This is a bad idea. Not all detected ESPs may belong to this system.<br>
> A correct solution requires to record the ESPs which are managed by this<br>
> system and must be updated.</div>
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Thank you for your patience as I learn how Debian hangs together. Is this an equally bad idea?</div>
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Get UUID of currently mounted <code>/boot/grub</code> with <code>CURRENT_UUID=$(lsblk -no UUID $(df /boot/grub | tail -1 | awk '{print $1}'))</code></div>
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Get UUID that `<code>grub.cfg` on the ESP I am looking at chains to with `</code>ESP_UUID=$(grep "search.fs_uuid" "$mnt"/EFI/debian/grub.cfg | awk '{print $2}')`</div>
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If the two match, this ESP is managed by this system and should be updated</div>
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The main point being whether comparing these two UUIDs is the right way to identify that an ESP is managed by the current system.</div>
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My tail and awk and grep stuff may well not be robust to get these two UUIDs in the first place.</div>
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Yours</div>
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Thorsten</div>
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