Best practices when using RegionServer grouping

You must keep in mind the following best practices when using rsgroups.

• Isolate system tables: You can either have a system rsgroup where all the system tables are present or just leave the system tables in default rsgroup and have all user-space tables in non-default rsgroups.
• Handle dead nodes: You can have a special rsgroup of dead or questionable nodes to help you keep them without running until the nodes are repaired. Be careful when replacing dead nodes in an rsgroup, and ensure there are enough live nodes before you start moving out the dead nodes. You can move the good live nodes first before moving out the dead nodes.

  If you have configured a table to be in a rsgroup, but all the RegionServers in that rsgroup die, the tables become unavailable and you can no longer access those tables.