So in short https://vyos.dev/T5440 will be broken again?

Nope, it works fine, now; your revision to the change re-broke it.

But before the revert by T5690 today T5440 worked perfectly fine so what was "re-broken"?

For below example I have installed 1.5-rolling-202310240118 with the custom name 1.5-CUSTOM-231024.

Suggestions (that is perform all 2 suggestions as mentioned below):

Let vyos_rootfs_dir be as the original pre T5461 was. That is let the revert in T5690 remain.

Example content:

/usr/lib/live/mount/rootfs/1.5-rolling-202310240118.squashfs

root@vyos:~# mount -t squashfs | cut -d' ' -f3
/usr/lib/live/mount/rootfs/1.5-rolling-202310240118.squashfs

Create a new variable and name it vyos_persistence_dir

Example content:

/usr/lib/live/mount/persistence/boot/1.5-CUSTOM-231024

root@vyos:~# cat /proc/cmdline | sed -e s+^.*vyos-union=++ | sed -e 's/ .*$//'
/boot/1.5-CUSTOM-231024

That is file https://github.com/vyos/vyatta-op/blob/current/etc/default/vyatta.in would have this added to create the variable mentioned in suggestion 2 above:

if test -z "$vyos_persistence_dir" ; then
    IMAGE_NAME=$(cat /proc/cmdline | sed -e s+^.*vyos-union=++ | sed -e 's/ .*$//')
    declare -x -r vyos_persistence_dir="/usr/lib/live/mount/persistence/${IMAGE_NAME}"
fi

Anyone against? :-)

This way we have vyos_rootfs_dir which is the mounted rootfs (filesystem.squashfs from ISO is renamed to the VyOS version during install/upgrade) which is readonly. Can be used as source to copy files and directories if needed.

And vyos_persistence_dir which is the actual directory on the permanent storage in the box running VyOS (which uses the custom name if such was selected during install/upgrade).

Update:

Looking through https://vyos.dev/T5457 I now get what you meant by "re-broke it".

The break comes with if the admin choose to use a custom name which the updated vyos_rootfs_dir didnt accounted for.

Will add a separate task for adding vyos_persistence_dir as a variable.

One way however to make the variable more robust in case there are for whatever reason more than one squashfs mounted object available is to select the one who is "loop0".

Like so:

if test -z "$vyos_rootfs_dir" ; then
    ROOTFS=$(mount -t squashfs | grep loop0 | cut -d' ' -f3)
    declare -x -r vyos_rootfs_dir="${ROOTFS}"
fi

PR created: https://github.com/vyos/vyatta-op/pull/79