Decrease a VM Disk Size

[netpage]

I've never used LVM before, after trying vgs and vgdisplay, I get nothing on on the screen, the command goes through but just blank.

 

[Kingneutron]

I've never used LVM before, after trying vgs and vgdisplay, I get nothing on on the screen, the command goes through but just blank.

I suggest you start a new thread, but if you used a ZFS-based boot/root instead of ext4 + LVM when you installed Proxmox, you're not even using LVM

You should also do some research into LVM if you want to use it - not having a grasp of the basics and trying commands blindly leads to pitfalls

 

[Dunuin]

not having a grasp of the basics and trying commands blindly leads to pitfalls

Especially when running commands like lvreduce that might destroy data...especially without the needed prequisites like shrinking filesystems and partitions on that LV first.
Thats also the reason why PVE webUI/API/CLI won't allow you to do that.