Local Replication is a process in which multiple copies of data are stored within a storage container. These copies exist for fault tolerance. Snapshots are placed locally on the same cluster as the source VM. Thus, If a physical disk fails, the cluster can recover data from another copy. The cluster manages the replicated data, and the copies are not visible to the user.
So, what is the difference the Replication Factor option? Because RF is used too for fault tolerance in case of a physical disk failure (or node, ...)
Best answer by HITESH0801
Local Snapshot is used if you want to restore your VM to a previous version using local snapshot, but RF copies are used for fault tolerance and are used to rebuild the data when a node or disk goes bad.
Replication of data happens at every write whereas snapshot get’s taken at a particular schedule.
Let’s consider two scenarios
1 → You have a local snapshot saved, and your VM got corrupted and you want to go to a previous version, you restore your VM using local snapshot.
2→ One of your physical disk goes bad, the data which was in the disk get’s rebuild(all happens behind the scenes ) and you have no data loss and your VM is totally fine. This happened because a duplicate copy of the data in the disk was stored somewhere else in the cluster and was used to rebuild the data. (Replication Factor in play).