This is a simple guide, part of a series I'll call 'How-To Guide Without Ads'. In it, I'm going to document how I set up
bcache on a Raspberry Pi, so I could use an SSD as a cache in front of a RAID array.
bcache is sometimes used on Linux devices to allow a more efficient SSD cache to run in front of a single or multiple slower hard drives—typically in a storage array.
In my case, I have three SATA hard drives:
/dev/sdc. And I have one NVMe SSD:
I created a RAID5 array with
mdadm for the three hard drives, and had the raid device
I then installed
$ sudo apt-get install bcache-tools
make-bcache to create the backing and cache devices: