I found one problem with the patch
The return type RegionOpeningStates has to be added in the map in HbaseObjectWritable otherwise IPC error is thrown saying unexpected code.
Is there any where else we need to change. Because i found a comment in the HRegionInterface saying that
any change done here we need to change the HBaseRPCProtocolVersion.java.
Do i need to change the version ?
One more thing is I tested the scenario that you had mentioned,
The Master had the patch whereas the RS did not have the patch. So whenever a region is opened it return a null value in the master side.
So there is no compatability problem but the scenario of partial enabling may not work.
Is it fine Stack? Do i need to verify any other thing?
I will resubmit the patch shortly.