We have a server with a volume Group (VG) and two logical volumes (LV). About two 11 days ago it worked fine and we could see information when we run "lvs -a" or "vgs -a", but now nothing is shown.

Hi:

We have a server with a volume Group (VG) and two logical volumes (LV). About two 11 days ago it worked fine and we could see information when we run "lvs -a" or "vgs -a", but now nothing is shown.
But if I run "lvs -a" or "vgs -a" or "lvdisplay" or "vgdisplay" I got no information.
Even if I run "lvs --help" or "lvdisplay --help", nothing is printed on screen.
It seems there is an error related to LVM, but We don't know what.
I have the error on dmesg "init: Failed to obtain startpar-bridge instance: Unknown parameter: INSTANCE"

About two 11 days ago it worked fine and we could see information when we run "lvs -a" or "vgs -a", but now nothing is shown.
I restarted the server and try several things but no luck.

Ubuntu versión is:
#lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 14.04.4 LTS
Release: 14.04
Codename: trusty

Version of lvm package is:
# dpkg -l | grep lvm
ii lvm2 2.02.98-6ubuntu2 amd64 Linux Logical Volume Manager

I can see the LV is mounted:
# mount | grep /opt
/dev/mapper/vg--opt--zimbra-lv--opt--zimbra on /opt type ext4 (rw)

There are LVs that they shouldn't exist:
# ls -l /dev/mapper
total 0
crw------- 1 root root 10, 236 Dec 11 03:13 control
lrwxrwxrwx 1 root root 7 Dec 11 10:27 vg--opt--zimbra-lv--opt--zimbra -> ../dm-1
lrwxrwxrwx 1 root root 7 Dec 11 03:13 vg--opt--zimbra-lv--opt--zimbra-real -> ../dm-0
lrwxrwxrwx 1 root root 7 Dec 11 10:27 vg--opt--zimbra-opt--snapshot -> ../dm-3
lrwxrwxrwx 1 root root 7 Dec 11 03:13 vg--opt--zimbra-opt--snapshot-cow -> ../dm-2

Too much devices in /dev/disk:
# ls -lR /dev/disk/
/dev/disk/:
total 0
drwxr-xr-x 2 root root 140 Dec 11 03:13 by-id
drwxr-xr-x 2 root root 80 Dec 11 03:13 by-partlabel
drwxr-xr-x 2 root root 80 Dec 11 03:13 by-partuuid
drwxr-xr-x 2 root root 100 Dec 11 03:13 by-uuid

/dev/disk/by-id:
total 0
lrwxrwxrwx 1 root root 9 Dec 11 03:13 ata-QEMU_DVD-ROM_QM00003 -> ../../sr0
lrwxrwxrwx 1 root root 10 Dec 11 10:27 dm-name-vg--opt--zimbra-lv--opt--zimbra -> ../../dm-1
lrwxrwxrwx 1 root root 10 Dec 11 10:27 dm-name-vg--opt--zimbra-opt--snapshot -> ../../dm-3
lrwxrwxrwx 1 root root 10 Dec 11 10:27 dm-uuid-LVM-6tkfLRvf42Y68M2Bcme0LzAeMzJja2HZ9E3YnxMBSQasz7G0mUkcWQa6tQhSmggA -> ../../dm-1
lrwxrwxrwx 1 root root 10 Dec 11 10:27 dm-uuid-LVM-6tkfLRvf42Y68M2Bcme0LzAeMzJja2HZCRr8AQtnx7QpnAjSCEp8Dikr7zapGgmL -> ../../dm-3

/dev/disk/by-partlabel:
total 0
lrwxrwxrwx 1 root root 10 Dec 11 03:13 primary -> ../../vdc1
lrwxrwxrwx 1 root root 10 Dec 11 03:13 PRIMARY -> ../../vdb1

/dev/disk/by-partuuid:
total 0
lrwxrwxrwx 1 root root 10 Dec 11 03:13 59ee8853-ae0e-4a7f-90d1-f1e5a8e4489d -> ../../vdb1
lrwxrwxrwx 1 root root 10 Dec 11 03:13 9669fe59-0ab9-4e5c-b559-3a5f7e70cbf0 -> ../../vdc1

/dev/disk/by-uuid:
total 0
lrwxrwxrwx 1 root root 10 Dec 11 03:13 5d485a10-6f17-48f6-b9a2-260b8aa09d49 -> ../../vda1
lrwxrwxrwx 1 root root 10 Dec 11 10:27 9aa61566-8f53-4201-8b74-8401ce4f3985 -> ../../dm-1
lrwxrwxrwx 1 root root 10 Dec 11 03:13 ee2649c4-818c-448f-aa9a-41dc42aad7b2 -> ../../vdc1

I tried to remove them with lvremove, but no error message nor other kind of information.

Any idea if this problem is related with the error on dmesg?
Any idea to resolve it?

Regards