[AMQ-4705] Add keep alive support to shared file locker

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 5.8.0
• Fix Version/s: 5.12.0
• Component/s: Message Store
• Labels: kahadb netapp nfsv4 shared-file-lock
• Assignee: Gary Tully
• Reporter: Gary Tully
• Created: 30/Aug/13 14:19
• Updated: 14/Oct/15 14:19
• Resolved: 03/Jul/15 11:40

Description

issue on nsfv4 with a master slave configuration, where both the slave and the master could obtain a lock.
The following events occurred:

• master locks the file - does no more i/o to it – it's passive wrt the lock
• slave asks every 10 seconds if it can get the lock nfs come back and say no, someone has it
• nfs dies not nicely
  • nfsv4 is stateful - no callback for locks.
  • It has a grace period of 30 seconds to let all clients that had locks reclaim them as locked
• master does not realize it needs to reclaim the lock and continues under the assumption it has the lock.
• After 30 sec grace period, slave comes in and asks for the lock and it receives it.

Issue Links

• is depended upon by: AMQ-5549 Shared Filesystem Master/Slave using NFSv4 allows both brokers become active at the same time
• is related to: AMQ-5568 Deleting lock file on broker shut down can take a master broker down