Backup plugin - how to exclude directories with FSArchiver?

I'm having a problem excluding directories, but only if run from backup plugin

Got the same behaviour for any directory.

Just for test, excluded /var/lib, that is about half the size of root fs.

Default fsarchiver settings, just added --exclude='/var/lib'

From backup plugin UI, manual run:

-[00][ 99%][REGFILE ] /var/lib/docker/volumes/fac8312a00a49722a0a1683584e28923ab9c57141b89bc946df21ebea93f11c1/_data/dump.rdb
-[00][ 99%][DIR     ] /var/lib/docker/volumes/585993a3ee79ce44f8783c49db710b7c01fb1ac135175d563cdb9234bbe39c3f
-[00][ 99%][DIR     ] /var/lib/docker/volumes/585993a3ee79ce44f8783c49db710b7c01fb1ac135175d563cdb9234bbe39c3f/_data
-[00][ 99%][REGFILEM] /var/lib/docker/volumes/585993a3ee79ce44f8783c49db710b7c01fb1ac135175d563cdb9234bbe39c3f/_data/dump.rdb
-[00][ 99%][DIR     ] /var/lib/docker/volumes/f751ce0e58b5b24f145e6fe5f58996591c1ad0de71e1cb095f3479527484497f
-[00][ 99%][DIR     ] /var/lib/docker/volumes/f751ce0e58b5b24f145e6fe5f58996591c1ad0de71e1cb095f3479527484497f/_data
-[00][ 99%][REGFILEM] /var/lib/docker/volumes/f751ce0e58b5b24f145e6fe5f58996591c1ad0de71e1cb095f3479527484497f/_data/dump.rdb
-[00][ 99%][DIR     ] /var/lib/pam
-[00][ 99%][REGFILEM] /var/lib/pam/password
-[00][ 99%][REGFILEM] /var/lib/pam/account
-[00][ 99%][REGFILEM] /var/lib/pam/seen

Obviously it is still compressing /var/lib and all contents.

Check the filesize - almost 4 GB:

ls -lh *.fsa
-rw-r--r-- 1 root users 3,9G lip  19 09:47 backup-omv-2025-06-19_09-46-55.fsa

This is a running backup process, seems ok, extra exclude option is appended:

ps -ef | grep fsarch
root       23115   22949 99 09:46 ?        00:00:07 fsarchiver savefs -o /srv/dev-disk-by-uuid-3067b496-644d-4574-9ac7-5fda7a0276f4/backup_omv/omvbackup/backup-omv-2025-06-19_09-46-55.fsa /dev/sda1 -v -A -Z 2 -j 4 --exclude='/var/lib'

Now, manual run as root via ssh, same cmd from above, just changed archive name:

fsarchiver savefs -o /srv/dev-disk-by-uuid-3067b496-644d-4574-9ac7-5fda7a0276f4/backup_omv/omvbackup/backup-omv-2025-06-19_manual_run.fsa /dev/sda1 -v -A -Z 2 -j 4 --exclude='/var/lib'

This time directory is excluded as expected.

Final archive sizes, notice how manual run with the same command is amost half the size.

ls -lh *.fsa
-rw-r--r-- 1 root users 3,9G lip  19 09:47 backup-omv-2025-06-19_09-46-55.fsa
-rw-r--r-- 1 root users 2,2G lip  19 10:32 backup-omv-2025-06-19_manual_run.fsa

Any ideas ?

How to exclude some directory from backup?

FSArchiver - Quick Start guide

Same problem with scheduled task and any excluded dir.

As i wrote in the first post, /var/lib was chosen just for test because it's large and easy to spot in the output of fsarchiver.

New info: if I run the script as root (/usr/sbin/omv-backup) it also does not exclude directory.

Now it gets interesting...

Setting exclude like this in settings doesn't work for me from scheduler or direct call of /usr/sbin/omv-backup:

--exclude='/some/directory'

But it works without the quotes

--exclude=/some/directory

The same principle for dir content: /some/directory/* works fine, but with quotes it does not.

Well, at least I can exclude dirs now

Enough testing... back to good old dd backup