Inspired by our article – SSD cache device to a hard disk drive using LVM, which uses SSD driver as a cache device to a single hard drive, we decided to make a new article, but this time using two hard drives in raid setup (in our case RAID1 for redundancy) and a single NVME SSD drive. The goal:
Caching RAID1 consisting of two 8T hard drive with a single 1T NVME SSD drive. Caching reads and writes, i.e. the write-back is enabled.
1 NVME SSD disk Samsung 1T. It will be used for writeback cache device (you may use writethrough, too, to maintain the redundancy of the whole storage)!
2 Hard disk drive 8T grouped in RAID1 for redundancy.
STEP 1) Install lvm2 and enable the lvm2 service
Only this step is different on different Linux distributions. We included three of them: Ubuntu 16+: