What Conditions Trigger the Voting Process for StorNext FS Failover?

Question:
What conditions trigger the voting process for StorNext FS failover in a file system only environment (No Storage Manager, no HA)?
 
Answer:
Either a StorNext File System client or a Network Security Services (NSS) coordinator (the systems listed in the fsnameservers file) can initiate a vote.
 
An SNFS client triggers a vote when its TCP connection to a File System Manager (FSM) is disconnected. In many failure scenarios, this loss of TCP connectivity is immediate, so it is often the primary initiator of a vote. On Windows systems, StorNext provides a configuration option called Fast Failover that triggers a vote as a result of a 3-second FSM heartbeat loss.
 
Occasionally, this is necessary because TCP disconnects can be delayed. There is also an NSS heartbeat between members and coordinators every half second. The NSS coordinator triggers a vote if the NSS heartbeat is absent for an FSM server for 3 seconds. Because the client triggers usually occur first, the coordinator trigger is not commonly seen.

 

Audience: 
Public Unrestricted
Review/Evaluate: 
2015-08-15
Document Type: