VM won't start due to io-error - how to increase disk space?

[jlauro]

It's worth noting that when you free up space in a vm, that typically doesn't free up space in the pool for other vms. The vms can generally grow from the thin pool, but generally not so good at returning space. It might be possible with trim support but I wouldn't count on it. So deleting files in the vm can keep that vm from needing to allocate more space, but don't count on it being available for other vms to reuse that temporary storage.

The root is the default place for I think ISO images that you upload and also backups. If you use that space sparingly (especially the backups) or setup a different drive for that, then 16GB should be plenty for root.

 

[teeeeee]

I managed to make progress on this problem:

As mentioned before, I had 59.6 GiB total on the disk, with 7.4 GiB for SWAP and 24.9 GiB on the Proxmox root partition. This should leave about 27GiB to work with. However, I was previously only seeing about 18.7 GiB to work with. I have managed to increase the available space by running the following command:

lvresize --extents +100%FREE --resizefs pve/data

I now see 27 G available on the local-lvm.

The second thing I did was to run

fstrim -a

on both my LXC container and my VM. This frees up several GB, and now I consume 13G, which is more like what is expected:



I think this makes more sense now.

 

[gfngfn256]

Happy you made progress. However I personally, would want a local-lvm that has enough space to manage the disks it contains, I think in your case this is 32gb(HA) & 10gb(LXC), so a total of at least 42gb. You only have 27gb.

 

[teeeeee]

@gfngfn256 Yes this makes sense to me, after learning from this thread. However, as I said before, I thought the whole point of "thin" storage was that you could have disks which add up to more than the local-lvm? Otherwise what is the point of using thin type storage, if one follows your preference of having a disk which is physically big enough anyway?

Thanks

 

[BobhWasatch]

@gfngfn256 Yes this makes sense to me, after learning from this thread. However, as I said before, I thought the whole point of "thin" storage was that you could have disks which add up to more than the local-lvm? Otherwise what is the point of using thin type storage, if one follows your preference of having a disk which is physically big enough anyway?

Thanks

Snapshots.

Over-provisioning storage is fine IF you keep careful track of usage so you don't run out. That can be catastrophic for your VM's. If you are the kind of person who just wants to just let it run and don't pay attention, don't over-provision.

 

[gfngfn256]

Snapshots.

Over-provisioning storage is fine IF you keep careful track of usage so you don't run out. That can be catastrophic for your VM's. If you are the kind of person who just wants to just let it run and don't pay attention, don't over-provision.

Exactly spot-on!
As I said previously, as an example, when Home Assistant updates itself, all sorts of things take place, and chances are you'll soon be looking at data-corruption.
I already stated, if you only have that 64gb SSD, PLEASE use a smaller /root, and increase you're local lvm!