Max VM Disk Size?

SUSE Virtualization
7

Yeah, sorry, I just wasn’t sure if you were using RAID for the Longhorn setup or not :slightly_smiling_face:.

It might be good to know exactly what you mean by disk corruption. It is at the physical disk level or at the Longhorn level?

  • Are you seeing degraded replicas? Are volumes failing to mount.
  • Is it at the disk level and you find yourself running xfs_repair often?
  • Are there specific I/O messages in the logs?

I agree that it is tricky to plan out your storage because you do need to allow for extra space for the data management overhead and it is somewhat dependent on knowing the average actual size of a Longhorn volume.

I have seen more issues with Longhorn when the disks are almost full. In my opinion, you need to set aside quite a bit of extra space to allow for the data management operations, but it is hard to determine exactly how much. The formula from the Longhorn documentation is only for a single volume. Once you have multiple volumes and their replicas being scheduled, it can be tricky to estimate accurately. Perhaps you can increase the storage-minimal-available-percentage parameter to ensure you have enough “buffer” space.