Configuring LVM storage for dynamic allocation of logical volumens

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1

Hi All,

I’m new to OpenNebula (6.8.0), so I may not be fully familiar with the terminology yet—please bear with me as I keep this basic.

I have a couple of bare-metal servers with several drives configured in RAID. The RAID volume is added to a single logical volume. What I’m aiming to do is dynamically create LVM volumes from this pool based on VM requirements. For example, if someone requests a 100 GB disk, I’d like to pass that configuration to OpenNebula and have it carve out the space from the existing LVM pool, assigning it directly to the virtual machine.

I’ve reviewed some documentation, but most of it refers to using LVM as an image store with NFS, which isn’t my use case.

Is this kind of setup possible? If so, could someone please point me to documentation or examples that align with this approach?

Thanks in advance!

2

Hello.

If I understand correctly, each server has it’s own disks in RAID, right?

In that case, you should use a distributed system like linstor which permits to replicate LVs using DRBD.

Or maybe the LVM is shared between each hosts? In this case, you have a lvm driver.

3

Thanks for the reply.

You’re right — I want to use these local disks for additional storage to improve performance. Currently, I’m using Ceph-backed storage, which hasn’t been very performant in my setup. From the volume group I’ve already configured, I’d like OpenNebula to dynamically carve out LVM volumes based on the disk requirements specified in each VM manifest.

4

i have logged a bug against addon-lvm project as well. here is the link to the bug.