CentOS - May 2016 - Centos 7.2: Mount one by one (not simultaneously!) two usb disk with same label

For backup, I have 2 usb disk with same label (LABEL=bove-bk) mounted
periodically one by one (not simultaneously!) in the same folder
/mnt/bove-bk/
> [root at s-virt ~]# grep bove-bk /etc/fstab
> LABEL="bove-bk"?/mnt/bove-bk?xfs?defaults,nofail 0 0
With Centos 5/6 this?has never given problems, now with c7 when I
unmount and unplug the first disk and I plug and mount the second I get
this message log and the disk is not mounted:
> [root at s-virt ~]# mount -a
> mag 18 10:18:20 s-virt.bove.local kernel: XFS (sdd2): Mounting V4
Filesystem
> mag 18 10:18:21 s-virt.bove.local kernel: XFS (sdd2): Ending clean mount
> [root at s-virt ~]# mag 18 10:18:21 s-virt.bove.local systemd[1]: Unit
mnt-bove\x2dbk.mount is bound to inactive unit
dev-disk-by\x2dlabel-bove\x2dbk.device. Stopping, too.
> mag 18 10:18:21 s-virt.bove.local systemd[1]: Unmounting /mnt/bove-bk...
> mag 18 10:18:21 s-virt.bove.local kernel: XFS (sdd2): Unmounting Filesystem
> mag 18 10:18:21 s-virt.bove.local systemd[1]: Unmounted /mnt/bove-bk.
In every way that I try to mount the disk (by UUID, into another
folder, using the device, ecc), always systemd Unmount my disk.

After some research I have found that by running these commands:
> [root at s-virt ~]# journalctl -f &
> [root at s-virt ~]# udevadm control --reload
> [root at s-virt ~]# systemctl daemon-reload
> mag 18 10:28:31 s-virt.bove.local polkitd[1035]: Registered Authentication
Agent for unix-process:25607:464417949 (system bus name :1.18421
[/usr/bin/pkttyagent --notify-fd 5 --fallback], object path
/org/freedesktop/PolicyKit1/AuthenticationAgent, locale it_IT.utf8)
> mag 18 10:28:31 s-virt.bove.local systemd[1]: Reloading.
> mag 18 10:28:31 s-virt.bove.local systemd[1]:
[/usr/lib/systemd/system/firstboot-graphical.service:14] Support for option
SysVStartPriority= has been removed and it is ignored
> mag 18 10:28:31 s-virt.bove.local systemd[1]: Configuration file
/usr/lib/systemd/system/auditd.service is marked world-inaccessible. This has no
effect as configuration data is accessible via APIs without restrictions.
Proceeding anyway.
> mag 18 10:28:31 s-virt.bove.local systemd[1]: Configuration file
/usr/lib/systemd/system/wpa_supplicant.service is marked executable. Please
remove executable permission bits. Proceeding anyway.
> mag 18 10:28:31 s-virt.bove.local polkitd[1035]: Unregistered
Authentication Agent for unix-process:25607:464417949 (system bus name :1.18421,
object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale it_IT.utf8)
(disconnected from bus)
the mount of second disk work property
> [root at s-virt ~]#?mount -a
> mag 18 10:28:36 s-virt.bove.local kernel: XFS (sdd2): Mounting V4
Filesystem
> mag 18 10:28:37 s-virt.bove.local kernel: XFS (sdd2): Ending clean
> mount[root at s-virt ~]#?
It's possible resolve this annoying issue and restore old c5/6 behavior
to allow a normal user to substitute the disks from graphical console?

Many thanks.

-- 
Dario Lesca
(inviato dal mio Linux Fedora 23 Workstation)

Il giorno mer, 18/05/2016 alle 12.05 +0200, Dario Lesca ha
scritto:
> For backup, I have 2 usb disk with same label (LABEL=bove-bk) mounted
> periodically one by one (not simultaneously!) in the same folder
> /mnt/bove-bk/?
> ...
> when I unmount and unplug the first disk and I plug and mount the
> second the disk is not mounted
I have try this scenario on a Fedora 23 and all work fine?

Is this a Centos 7 bug?
It's better I fill a bug?

Thank for your suggest.

-- 
Dario Lesca
(inviato dal mio Linux Fedora 23 Workstation)