Reducing VM capacity

Hi guys,

I'm new to unraid and still playing around but I'm having an issue with an Ubuntu VM.

I am playing around with LVM trying to learn how it all works and every time I try and reduce the disk size the VM fails to boot showing this message:

ALERT! /dev/mapper/ubuntu--vg-ubuntu--lv does not exist.

So here is the steps I've taken

1. Installed Ubuntu (with 1T from unraid)

2. Extended the LVM to full size using these commands:

• lvextend -l +100%FREE /dev/mapper/ubuntu--vg-ubuntu—lv
• resize2fs /dev/mapper/ubuntu--vg-ubuntu—lv
• This works fine and all is good

3. Reduced the LVM now using this command: (this is also from a live CD so I can resize the root partition)

• sudo lvreduce --resizefs -L 400G /dev/mapper/ubuntu--vg-ubuntu—lv
• Then opened gparted and resized the partition to 400G

Reboot into the server and everything is working perfectly, the size is now 400G.

However I now want to reduce the actual disk size, so I go into unraid and click on the VM name to show the drives and change the capacity from 1T to 500G. Giving me an extra 100G as buffer. When I do this and boot the VM up it doesn't boot into Ubuntu and gives me that alert error (ALERT! /dev/mapper/ubuntu--vg-ubuntu--lv does not exist.)

So can anyone who has more experience help me out here.

Thanks in advance