I want to set up a RAID 5 with 3x1TB drives on a Linux KVM-Host. The RAID will be used as LVM thin storage for VM disks.
There has already been much discussion on hardware raid vs software . According to this discussion one should not use software raid but hardware raid with cache and BBU for VM disk storage because of the better write performance.
What I would like to know is if the following setup would be comparable to a hardware raid with cache and BBU (e.g. HP P410 512 MB + BBU) in terms of read/write performance and data safety:
- Linux Software RAID / mdadm RAID 5
- LVM writeback cache on a 512 MB ram disk
- Host backed by UPS to prevent data loss like the BBU on hw raid