It is possible to configure remote data replication at many layers of the storage stack. Some examples to explain what I mean by layers:
- Physical Volume Layer (TruCopy, SRDF/MirrorView, SnapMirror)
- Virtual Server Layer (vReplicator, Veeam)
- Logical Volume Layer (VVR, AVS)
- Filesystem Layer (Rsync, ZFS Send/Recv)
- Application Layer (Data Guard, MySQL/PostgreSQL Replication, AD Replication)
Replication at each layer has a unique value proposition but it would be crazy to use them all. My particular problem is the proliferation of different solutions; I'd like to standardize on one or two solutions in order to keep down license costs, complexity, and expertise requirements.
My question is: ignoring the individual product examples, which layer or combination of layers of replication provide the most value in a typical corporate environment, and which are becoming more valuable?
Possible metrics include ease of administration, availability of expertise, protection from data corruption, recovery time/complexity in a DR scenario, reduction in planned outage windows, application performance, application flexibility, and anything else that might be valuable.
This is a question I encounter often as a system administrator so I would appreciate any advice.