Re: HOWTO: USB boot on 8 GB RPi4 with no SD card

[mlelstv%serpens.de@localhost (Michael van Elst)]

bsd-lists%gromit.dlib.vt.edu@localhost (Paul Mather) writes:

>It's probably confusing, but I wasn't suggesting 64K block and 8K fragment sizes are invalid, just that I've never seen FFS file systems created with blocks that big. :-)  (I wonder what the maximum allow size is?  The newfs man page tops out at 32K.)

While FFS could use larger blocks, we are limited to MAXPHYS, which is
currently 64k.

You can have up to 8 fragments per block, so 64k/8k is maximum.


>I guess this works in practice because during boot the mount is initially read-only.  Then, the resize_gpt and resize_root services will operate and I guess this fixes the problem with the root FFS file system being bigger than the partition in which it lives.

Still a bug in generating that image. It will also fail if the missing
blocks actually carry content.

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                                Michael van Elst
Internet: mlelstv%serpens.de@localhost
                                "A potential Snark may lurk in every tree."