Peter via Dng said on 30 Nov 2025 05:55:57 -0700

>From:    Steve Litt <slitt@???>
>Date:    Sat, 29 Nov 2025 21:58:28 -0500
>> ... Ext4 or btrfs etc is good enough for me.
>> ...
>> Let's say your boot drive is a single partition on an NVMe. You 
>> install your OS on that, as THE single partition.  

>
>Good tutorial. Thanks! Stored in the SteveLitt file here.
>
>(1) Often the orginal system is on /dev/sda. For blunder avoidance,
>will translate "/dev/sda" to "/dev/sd<somethingElse>" before messing
>with commands.
>
>(2)
>> The real beauty is when you add a few other directories, which
>> used to be mountpoints. Instead of you having to guess how much
>> they'll hold, you can just symlink them to corresponding directories
>> under /bindmounts, and you'll have former mountpoints that are now
>> completely expandable and shrinkable.
>
>Good.
>
>Suppose you add another device, /dev/sdb. You can't have a directory
>spanning /dev/sda and /dev/sdb. Correct?

Absolutely correct. But how often do you really need that capability?
How often do you need that much space in a single level of a single
directory? Don't forget, you can have the directory tree on
/bindmounts_disk1 and the maildir directory under it on
/bindmounts_disk2 . One can always theoriticize a use case for LVM,
where directories and "partitions" are completely loosey goosey, but my
view is the complexity cost of LVM far outweigh fixable edge case
hassles with bind mounts.

I don't know which list, but on some Linux list I read a guy's plea for
help after his LVM got messed up. Let's just say it wasn't pretty.

>
>All I know about overlayfs is from Wikipedia.
>https://en.wikipedia.org/wiki/OverlayFS
>Reaches a result similar to yours? Allows a directory to span
>multiple devices? Another gadget to try when there's time to spare.
>=8~/

My reading of your referenced URL plus some others tells me that these
multiple sources might just be read-only versions of what you're
writing to, but I can't be sure due to the wording.

Anyway, the fact is that you can achieve rubber-walled directories from
bind mounts in a very simple, all Linux no frills manner. I'm sure one
could hypothesize "but does it do ____________". This "but does it do
____________" is exactly the argument used by the systemd cabal,
typically with _________ being a rarely used thing. Seatd? Who runs
monitors for different people to one commodity computer in 2025 or even
2014? "but does it do ____________" is the typical way the
complexity camel gets its nose in your simple and modular tent. Anyway,
my reading tells me that overlayfs is intended for a very different
usage: A computer running on a read-only driver or ram-drive or
initramfs.

My advice comes from the Walker Brothers: Make It Easy On Yourself!

https://www.youtube.com/watch?v=El8fHMBXRy8

Break up with these megalayers, and get down to what works.

SteveT

Steve Litt

http://444domains.com