How to do rolling upgrade of a hadoop cluster with hbase?

[Debraj Manna]

I am having a cluster like below


   - 3 Hbase Master (1 Active & 2 standby)
   - 4 Region Servers
   - 4 Data Nodes
   - 1 Primary & 1 Secondary Name Node
   - 3 Journal Node
   - 4 Nodemanager
   - 3 Resource Manager (1 Active & 2 standby)


Can someone let me know how can I plan a rolling upgrade of the above
cluster with minimum downtime?


   - Hadoop - 2.6.0
   - Yarn - 2.6.0
   - Hbase - 1.2.0

Thanks,