[HADOOP-12650] Document all of the secret env vars

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Won't Fix
• Affects Version/s: 3.0.0-alpha1
• Component/s: scripts
• Assignee: Unassigned
• Reporter: Allen Wittenauer
• Created: 16/Dec/15 13:49
• Updated: 01/Sep/18 20:23
• Resolved: 01/Sep/18 20:23

Description

Over the years, developers have added all kinds of magical environment variables in the Java code without any concern or thought about either a) documenting them or b) whether they are already used by something else. We need to update at least hadoop-env.sh to contain a list of these env vars so that end users know that they are either private/unsafe and/or how they can be used.

Just one of many examples: HADOOP_JAAS_DEBUG.

Issue Links

• relates to: HADOOP-12649 Improve Kerberos diagnostics and failure handling