CIVICRM with MYSQL encrypted on ecryptfs
Linking to your other question which is similar but slightly different since it's about using encryption that's natively supported by mariadb: Civicrm on mariadb with data encryption.

For this question, I have used a similar tool encfs once for a non-civi setup to put the mysql files on an encrypted partition and it worked fine but the problem I had was the same as in the other post, that it partly defeats the purpose if you have to store the keys/password unencrypted on the same server, or else you can't do unattended reboots. It's a trade-off.