ok after digging for hours i found the problem.
Aug 21 10:11:38 storage systemd[1]: Starting Execute the rsync backup jobs when /dev/disk/by-label/hive-backup is plugged in...
Aug 21 10:11:39 storage rsync-92885e69-e67b-479a-9afd-d7c98ef4f1e2: Please wait, syncing '/srv/dev-disk-by-label-HIVE/hive/' to '/srv/1340c93155d2dc297e79165be195dec2/hive' ...\n
Aug 21 12:09:42 storage openmediavault-usbbackup-1340c93155d2dc297e79165be195dec2[16302]: rsync error: received SIGINT, SIGTERM, or SIGHUP (code 20) at rsync.c(644) [sender=3.1.2]
Aug 21 12:09:42 storage openmediavault-usbbackup-1340c93155d2dc297e79165be195dec2[16302]: rsync error: received SIGINT, SIGTERM, or SIGHUP (code 20) at io.c(513) [generator=3.1.2]
Aug 21 12:09:45 storage systemd[1]: Started Execute the rsync backup jobs when /dev/disk/by-label/hive-backup is plugged in.
Aug 21 13:10:10 storage avahi-daemon[27925]: Loading service file /services/rsync.service.
Aug 21 13:10:12 storage avahi-daemon[27925]: Service "storage - Rsync" (/services/rsync.service) successfully established.
Aug 21 15:40:01 storage cron[588]: (*system*openmediavault-rsync) RELOAD (/etc/cron.d/openmediavault-rsync)
So the usb-backup addon thinks the raid system is a removalble or at least its triggering the rsync command and this is what id all that.
The dist upgrade from wheezy to jessie and later the upgrade from omv 3 to 4 may have had to extensive changes. For one the change to "disk-by-label"
and there is a second raid drive presend with the old config. Looks like i have to reinstall.
If there is anyone who is willing to help and fix it i would appriciate it.
thx in advance