Question: A bit like other questions on touchpads but with a twist, I think. The touchpad in this Lenovo IdeaPad Z360 had been acting up even when it ran Windows 7. I switched to an external USB optical mouse, but the thing often disappears, buttons stop working or pointer starts moving on its own. 

xinput lists the following pointer devices:

```
⎡ Virtual core pointer                      id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ USB OPTICAL MOUSE                         id=10   [slave  pointer  (2)]
⎜   ↳ PS/2 Generic Mouse                        id=14   [slave  pointer  (2)]

```

"USB OPTICAL MOUSE" is external mouse. Is it possible that the two devices are fighting for control of the pointer and buttons? How can I disable "PS/2 Generic Mouse" and leave "USB OPTICAL MOUSE" reign unchallenged?

Answer: 
steeldrivers suggestion worked perfectly!

```
sudo mount /dev/mapper/vg1000-lv /mnt

```

still unmounting never got fixed, but got it all copied over the network and disks were formatted so, that got that solved.
I am not an expert on LVM or mdadm but here's what I did to solve a related problem on Ubuntu 18.

A single hard drive SHR attached trough USB-SATA adapter. The system tries to automatically set the RAID volume, but something goes wrong:

If I try to assemble:

```
mdadm -Asf && vgchange -ay

mdadm: Found some drive for an array that is already active: /dev/md/DiskStation:2
mdadm: giving up.
mdadm: No arrays found in config file or automatically

```

or `mount`:

```
mount /dev/mapper/vg1000-lv /mnt/
mount: /mnt: can't read superblock on /dev/mapper/vg1000-lv.

```

I have checked and the system already mapped a `/dev/mdXXX` to the SHR drive. So:

```
dmsetup remove /dev/mapper/vg1000-lv

mdadm --stop /dev/mdXXX

```

And after it's possible to retry to assemble with mdadm:

```
mdadm -Asf && vgchange -ay

```

The mount reference is under `/media/xxxxx/volumeToMount`