Streams on RAC
Posted: May 5, 2009 Filed under: rac, streams 5 CommentsWe had RAC system as streams source for 18 month now. But just today I configured a RAC as streams target.
It was somewhat of an anticlimax since there is absolutely nothing interesting to do.
We do downstream capture, so I had to place the archive logs on a shared drive. Every place where I used the SID before, I now used the DB name.
Capture and Apply processes both started on the same node. When I stopped that node, I saw the other node modifying a service called SYS${streams user}.{streams queue name}.{target db name}’ , changing it to run on the remaining node.
Then the capture and apply processes started on the remaining node and everything continued as usual.
As I said, no big deal. I just wanted to let everyone know that it is no big deal.
Just a simple Hadoop DBA 
Nice to know that it works together. I know most of us have experienced their share of sparks flying when trying to mesh two major features.
I had that experience too. That is why I was nicely surprised when it worked 🙂
The only Addition in RAC/streams is that the node location of the Streams process(capture or apply) is determined by the node location of the associated Queue table.
There is also an erratic behavior: When a queue perform a forced failover to another node, it does not come back automatically on the original node after this last one comes back. This is expected. However, I could observe that sometimes the queue reverse by its own. Up to now I could not derive a precise rule on this behaviaor.
Yes. Queue table has node affinity and the processes will match that. The entire move seems to be managed by the “services” system. I did not see the queue move on its own yet and this sounds rather disturbing, since the processes will restart when this happens (as part of the move). I noticed that queues can be configured to start on a specific node. Maybe using this feature can solve the issue?
Can you Suggest the Whatever thing We need to take care for implement Bidirectional the Stream over between RAC database and Local Database.
Thanks in Advance
Hitesh