[YARN-4789] Provide helpful exception for non-PATH-like conflict with admin.user.env

• Type: Bug
• Status: Patch Available
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.7.2
• Component/s: client
• Labels: oct16-hard
• Assignee: Gera Shegalov
• Reporter: Gera Shegalov
• Created: 11/Mar/16 10:18
• Updated: 27/Oct/16 18:47

Description

Environment variables specified in mapreduce.admin.user.env are supposed to be paths (class, shell, library) and they can be merged with the user-provided values. However, it's also possible that the cluster admins specify some non-PATH-like variable such as JAVA_HOME. In this case if there is the same variable provided by the user, we'll get a concatenation that does not make sense and is difficult to debug.

Issue Links

• relates to: MAPREDUCE-6491 Environment variable handling assumes values should be appended