[SLIDER-85] Slider AM to recognise & fail when another instance of the same name is up.

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: Slider 0.30
• Fix Version/s: Slider 2.0.0
• Component/s: appmaster, registry
• Assignee: Unassigned
• Reporter: Steve Loughran
• Created: 20/May/14 11:36
• Updated: 02/Oct/14 18:36

Description

using the YARN app reports to enumerate instances before launching has a race condition two attempts to deploy the same application instance could be made. If neither operation was visible in the queue when it was polled, they'd both get in

All HBase/accumulo instances would join up to form an aggregate cluster, which could be confusing, and complicate other operations like "stop".

The registry can be used to fix this: if there is an instance already of that name, the AM should fail