[HADOOP-8007] HA: use substitution token for fencing argument

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0.0-alpha
• Fix Version/s: 2.0.0-alpha
• Component/s: ha
• Hadoop Flags: Reviewed
• Target Version/s: 2.0.0-alpha
• Assignee: Todd Lipcon
• Reporter: Aaron T. Myers
• Created: 30/Jan/12 22:11
• Updated: 23/May/12 21:15
• Resolved: 04/Apr/12 09:27

Description

Per HADOOP-7983 currently the fencer always passes the target host:port to fence as the first argument to the fence script, it would be better to use a substitution token. That is to say, the user would configure "myfence.sh $TARGETHOST foo bar" and Hadoop would substitute the target. This would allow use of pre-existing scripts that might have a different ordering of arguments without a wrapper.

Issue Links

• is related to: HDFS-3084 FenceMethod.tryFence() and ShellCommandFencer should pass namenodeId as well as host:port
• relates to: MAPREDUCE-4103 Fix HA docs for changes to shell command fencer args