Data Protection
Snapshots
Snapshot Advantages
• Snapshots are a relatively “impact-free” replication
technique
• Only original data that has been changed is copied
• Snapshot process runs independently of application I/O
Pros Cons
Minimal impact on Snapshot data set is
application performance never 100% up to date
Minimal use of SAN No protection against
bandwidth disk failure
Point-in-time copy Relies on Primary
protects against storage still being
corrupted data available
Only original data that has been changed is copied, it relies on the primary
volume, so minimal impact on application performance because this is all
happening inside the subsystem.
Minimal use of SAN bandwidth. It’s in-system replication and it can protect us
against corrupt data because it’s a point in time copy. As long as we took our
snapshot before the corruption occurred, we can roll back to before the
corruption occurred.
The downside is that it is a snapshot. It’s never 100% up to date. It’s a point
in time copy and there’s no protection against disk and primary volume failure
because this relies on accessing the original logical unit for the original data.