Five Years of Btrfs
A question for HN: what filesystem and/or block-device abstraction layer would you use on a database server, if you wanted to perform scheduled incremental backups using filesystem-level consistent snapshotting and differential snapshot shipping to object storage, instead of using the DBMS’s own replication layer to achieve this effect? (I.e. you want disaster recovery, not high availability.)Or, to put that another way: what are AWS and GCP using in their SANs (EBS; GCE PD) that allows them to take on-demand incremental snapshots of SAN volumes, and then ship those snapshots away from the origin node into safer out-of-cluster replicated storage (e.g. object storage)? It it proprietary, or is it just several FOSS technologies glued together?My naive guess would be that the cloud hosts are either using ZFS volumes, or LVM LVs (which do have incremental snapshot capability, if the disk is created in a thin pool) under iSCSI. (Or they’re relying on whatever point-solution VMware et al sold them.)If you control the filesystem layer (i.e. you don’t need to be filesystem-agnostic), would Btrfs snapshots be better for this same use-case?