Recommendations

Software RAID (mdraid) with volumes

Since they provide a block device interface, volumes can be used to create software RAID (mdraid) devices.

While this is usually sensible when using physical disk devices to increase reliability, create volumes bigger than the size of drive, or improve IO performance, it typically does not make sense to use this strategy with block volumes.

Data stored in volumes is replicated in the backend to avoid loss in the event of hardware failure. Also, volumes can be created with arbitrary sizes and existing types varies performance, supporting also higher IO demands.

Depending on the RAID level, RAIDing volumes can even have a negative impact as all IO goes over the network and some transactions, such as small writes, require preceeding read operations.

If in doubt with the use of volumes in combination with RAID, please get in touch by opening a service desk ticket.