On 9/23/22 12:50, Tim Gorman wrote:
Chris,
Whether you're on-prem or in cloud...
* RAC, RAC one-node, and OS-level HA clusters (i.e.
Pacemaker/Corosync, etc) provide protection only to the /database
//service/, not to the /data/ in the database/
/
o RPO isn't a factor with service protection, as RPO is a
characteristic of /data protection//
/
* Restore/recovery from database backups can not guarantee RPO lower
than the initialization parameter setting for ARCHIVE_LAG_TARGET
o ...and there are many reasons to consider RPO to be at least
twice the ARCHIVE_LAG_TARGET value as well...
* Data replication utilities like GoldenGate, SharePlex, etc cannot
guarantee RPO=0 due to all the queuing and forwarding necessary
o "/eventual consistency/" also implies that "/eventual/" could
turn out to be "/never/"
The only Oracle mechanism which guarantees RPO=0 is DataGuard using MAX PROTECTION mode, while DataGuard in MAX AVAILABILITY mode comes in with a close second.
Even the Zero Data Loss Recovery Appliance (ZDLRA) essentially employs the same mechanisms used by DataGuard MAX PROTECTION mode.
Please let me know what you think?
Thanks!
-Tim
