OTN Appreciation Day: Oracle Data Guard and DG Broker
Thanks to Tim Hall for organizing this day – I’m happy to give back to the community which has given me so much.
My favorite feature is with no doubt is the Data Guard.
Even though the Data Guard feature might looks like an excess of other features (redo log for recovery, archive log for backup) it is one of the more awesome features in the Enterprise Edition database.
For those of you who don’t know what I am talking about – Data Guard is the disaster solution feature for the Oracle Database. This feature has been around since Oracle 7 (under the name Standby Database), but in Oracle 10g it had a major change: for the first time there was a way to create disaster recovery solutions, which actually had ROLES in them!
So why this is so exciting, you might ask. Well, that meant that not like the standby database that came before, you could now tell the database it is part of a DR solution – and decide which of your instances is the primary database, which is the standby, and have multiple standbys at the same time!
This alone made this feature exciting – but Data Guard is just keep on growing. For example: in Oracle 11g they added the ability to open the standby database at a Read Only mode (Active Data Guard). In Oracle 12c they changed it again to allow more operations on the active (yet R/O) standby like working with the sequences and global temporary tables – and it’s just keep on growing and changing!
Adding to the dataguard mechanism the data guard broker feature, and you get a complete solution for role transitions and operation. With a single command, you can now control planned events (using switchover) and unplanned events (like failover and reinstate) and that made life much easier…
Another thing I like very much is the snapshot standby. Snapshot standby is the ability to open your standby database as a read-write instance and then revert it back to standby with a single command. That’s awesome – the first time I helped a customer move from his many-scripts-solution to this single line solution – and seeing his face when it all worked flawlessly: that was all worth it.
Enough about data guard – I now sound like a total Oracle Geek (which is okay, because I am… 🙂 )
For more information about data guard:
Great Post Zohar! Absolutely agree with you that Data Guard is super cool ! 🙂