VVR For Oracle with several DGs as part of SF HA/DR
Created: 20 Oct 2012 | Updated: 21 Oct 2012 | 5 comments
This issue has been solved. See solution.
I know this has been discussed several times in this forum in the past, but I have yet to find an answer that provides sufficient information to my situation.
I am currently setting up a DR configuration for three Linux servers running Oracle 10g - two in the primary site and one in a DR site.
The two servers in the primary site are running Oracle in an SF HA configuration (version 5.1 SP1 RP2) and due to customer request, the Oracle data is split between several Disk Groups - Oracle Data DG, Oracle Archive DG, Oracle Temp DB DG, Oracle Redo A DG and Oracle Redo B DG.
Customer wants to replicate all the above Disk Groups (there's also a backup DG and a software DG which won't be replicated) and has sufficient storage for SRL and network bandwidth to perform the replication in a-sync mode in addition to configuring VCS Global Cluster to control all the configuration during DR failover.
I have completed all the setup required between both sites and have only one question I haven't been able to answer:
I understand how VVR works with SRL to ensure that writes on the secondary are performed in the same order as they were in the primary, and I know that for flat files applications, if the secondary is consistent (which it should usually be) I can failover to the DR site and might have a certain data lose but still be able to bring the application online.
My question is, if I have several DGs for Oracle DB, how can I make sure that the Database at the DR site will be consistent and will be brought online successfully by VCS when the primary crashes or when the network is disconnected between sites (I'm not referring to manual DR failover).
Can I expect to find the DB on the DR site in a status in which I have to manually perform operations with Redo logs or control files checkpoints to bring the DB online?
Is there any special attributes in VCS I should make sure to configure in order to support said situations?
As I am not a DB admin, I don't fully understand how Oracle behaves in certain situations.
Any advice would be much appreciated.