Beginner storage confusion and io-error

[lasciousfloy]

First off, I apologize for a question I have seen many times in this forum, but I cannot seem to make heads or tails of my situation from previous threads.

I have a VE set up mainly to run Home Assistant as well as tinkering/testing with Linux. Yesterday I ran into the infamous io-error as my lvm-thin ran out of space. I deleted a snapshot to free up space, and everything is back online.

After doing some digging into my storage allocations, I have gotten myself confused as I cannot seem to rectify all of the numbers provided in the various areas (see screenshots).

If it's possible, I will resize lvm-thin, as I don't plan on adding any other VMs than what I currently have. I am unsure though, of whether that is going to give me more headaches at best or break something at worst.

I have looked through the Proxmox wiki on storage as well, but I am still a little bit in the dark as to the best way forward.

Any help with this would be greatly appreciated.

 

[dakralex]

I'm not entirely sure if I understood what you're confused about exactly, but if it is about the usage of the disks the screenshots seem alright to me.

A common pitfall is that it isn't always exactly obvious that on standard installations with ext4 filesystems, the LVM volume group pve is placed on the single disk partition /dev/sda3 and the local and local-lvm storages (which are created as the logical volumes pve-root and pve-data respectively) are part of the pve volume group. Screenshot lvm-8.png shows how much of the disk is allocated to the logical volumes and therefore does not mean that the disk is full, but the volume group is.

I hope this clarifies it a little bit more. If you have any other questions, feel free to ask here.

 

[lasciousfloy]

I'm not entirely sure if I understood what you're confused about exactly, but if it is about the usage of the disks the screenshots seem alright to me.

A common pitfall is that it isn't always exactly obvious that on standard installations with ext4 filesystems, the LVM volume group pve is placed on the single disk partition /dev/sda3 and the local and local-lvm storages (which are created as the logical volumes pve-root and pve-data respectively) are part of the pve volume group. Screenshot lvm-8.png shows how much of the disk is allocated to the logical volumes and therefore does not mean that the disk is full, but the volume group is.

I hope this clarifies it a little bit more. If you have any other questions, feel free to ask here.

Thanks for getting back to me, and explaining the layout of the filesystem structure.

I think I have a bit better understanding on how the disks and groups are allocated by proxmox now.

The thing I still want to sort out is, my original problem was the local-lvm was maxed out at 152.3 GB until I deleted a snapshot. I want to (if it's possible) expand that allocation to avoid a similar issue in the future. I'm still a little unsure on how expanding it will affect the rest of the installation.

Thanks again for your time,
Ben

 

[waltar]

Thanks for getting back to me, and explaining the layout of the filesystem structure.

I hope you are getting right as most of pve storage is mostly NOT in a filesystem and exactly this part (of data) leads again and again to confusion and it's the same of if it's zfs or the lvm+lvm-thin couple is "the unknown space problem".
PS: But it's not a must and obviously you can instead layout all vm/lxc in any kind of real filesystem (local or remote) also.