[HBASE-13453] Master should not bind to region server ports

• Type: Improvement
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Fix Version/s: 1.1.0, 2.0.0

Release Note

In 1.0.x, master by default binds to the region server ports (both rpc and info). This change brings back the usage of old master rpc and info ports in 1.1+ and master (2.0) branches. The motivation for this change is to ease the life of the user so that he does not need to do anything to bring up a RS on the same host and also to make the migration from 0.98 to 1.1 hassle free. However, the users going from 1.0 to 1.1 would see the change in the master ports.

• Assignee: Srikanth Srungarapu
• Reporter: Enis Soztutar
• Created: 10/Apr/15 18:57
• Updated: 03/Jun/15 15:28
• Resolved: 15/Apr/15 18:07

Description

In 1.0, master by default binds to the region server ports (rpc and info). We have done it so thinking that in the long term, master and meta co-location will be default, and we can merge the master and region server as a single daemon.

Over at HBASE-11165, if the conclusion end up being that meta will not be colocated at all, then master hosting a region server will just become an implementation detail. [e-mail] says that we might never allow master to host regions.

Now, we are stuck in a state where we have made master bind to RS ports in 1.0, which might create some confusion (and frustration) for small cluster users who traditionally used to host a master and a region server on the same node.

I think we should undo this in 1.1 and use the previous master ports (16000) and not bind to 16030, so that the user does not need to do anything to bring up a RS on the same host. At least users going from 0.98 -> 1.1 will not take a hit. Users going from 1.0 -> 1.1 will see changed default ports.

Sub-Tasks

• Document the change of default master ports being used .: Closed
• [branch-1.0] Master should not bind to region server ports: Closed
• Master should respect master (old) DNS/bind related configurations: Closed