****Confidential Information**** Subject to the terms and conditions of the Master Software Beta Test Agreement & Program Rules you have previously accepted VMware vSphere Beta 2 Program Q&A Session – NFS Client Webinar Thursday, July 31, 2014 ________________________________________________________________ Q: Will there be a new or improved all path down handling we have had issues with this since moving to 5.1 and 5.5 A: First the all path down caused by clock skew is resolved in 6.0 for both NFSv3 and NFSv4.1. Second NFSv4.1 adds multipathing support. IO can failover to other paths if one path goes down. There is no more single point failure in path access with this new multipathing feature. ________________________________________________________________ Q: If there is no file lock, how does that affect datastore heartbeats? A: In case there is no activity, for NFSv4.1 there are session level heartbeats that tell the server that we the client is alive. A: There is no heartbeat for lock. This is stateful. Lock is kept by session. As far as session lease is valid, datastore is valid. Sure, we need to release session lease by a heartbeat like thing. ________________________________________________________________ Q: How does the session level heartbeat mechanism work? A: The client and server keep a session lease. Session does not need heartbeat to demonstrate liveness. Before the lease expires, client renews the session lease. ________________________________________________________________ Q: Is NFSv4.1 sync or async? A: Both. For data IO (read or write) it is handled async. For data operations (open, closed, rename, etc), those are synchronous. ________________________________________________________________ Q: Would there be any issue with array based replication or file based replication between v3 and v4?

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****Confidential Information**** Subject to the terms and conditions of the Master Software Beta Test Agreement &

Program Rules you have previously accepted

VMware vSphere Beta 2 Program Q&A Session – NFS Client Webinar

Thursday, July 31, 2014 ________________________________________________________________ Q: Will there be a new or improved all path down handling we have had issues with this since moving to 5.1 and 5.5 A: First the all path down caused by clock skew is resolved in 6.0 for both NFSv3 and NFSv4.1. Second NFSv4.1 adds multipathing support. IO can failover to other paths if one path goes down. There is no more single point failure in path access with this new multipathing feature. ________________________________________________________________ Q: If there is no file lock, how does that affect datastore heartbeats? A: In case there is no activity, for NFSv4.1 there are session level heartbeats that tell the server that we the client is alive.-‐ A: There is no heartbeat for lock. This is stateful. Lock is kept by session. As far as session lease is valid, datastore is valid. Sure, we need to release session lease by a heartbeat like thing.-‐ ________________________________________________________________ Q: How does the session level heartbeat mechanism work? A: The client and server keep a session lease. Session does not need heartbeat to demonstrate liveness. Before the lease expires, client renews the session lease. ________________________________________________________________ Q: Is NFSv4.1 sync or async? A: Both. For data IO (read or write) it is handled async. For data operations (open, closed, rename, etc), those are synchronous.-‐ ________________________________________________________________ Q: Would there be any issue with array based replication or file based replication between v3 and v4?

A: No issues as long as 1) Data is not accessed concurrently across NFSv3 and NFSv3.1, and 2) Be aware of the permission issues in case using Kerberso from NFSv4.1. -‐