[MAPREDUCE-6592] MR ApplicationMaster is not supposed to resolve rack locality! It should ask RM or NN about the topology

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Duplicate
• Assignee: Harsh J
• Reporter: Babak Behzad
• Created: 28/Dec/15 22:45
• Updated: 29/Dec/15 10:14
• Resolved: 29/Dec/15 10:14

Description

While working on configuring Rack Awareness (following HDP Documentation), we realized that this does not work for MR applications, unless the rack topology resolution script is installed on the node managers where the application masters reside. Otherwise, the AM will thrown an IOException: Cannot run program "/etc/hadoop/conf/rack_topology.sh".

This is contradictory to the documentations which states it makes sense to have the scripts that resolve the rack and node names on the Resource Manager and Name Node.

It is clearly not scalable to require to install these scripts on all the node managers!

Issue Links

• duplicates: YARN-435 Make it easier to access cluster topology information in an AM