What is a Dell recommendation when connecting ESXi hosts to PowerStore?

For file-based vVol datastores on PowerStore, Dell's best practice is to configure a minimum of two NAS servers. This architecture involves creating one NAS server on each node of the PowerStore appliance. This setup provides high availability and load balancing for NFS traffic from the ESXi hosts. If one PowerStore node or its network path becomes unavailable, the vVol datastore remains accessible through the NAS server on the other node, ensuring continuous operation for the virtual machines.

A. The recommended IOPS limit for Round Robin multipathing with PowerStore is 1, not 1024. An IOPS limit of 1 ensures I/O is distributed more frequently across all active paths.
B. Dell explicitly recommends disabling DelayedACK for iSCSI connections. Enabling it can introduce latency and negatively impact storage performance.
D. For optimal NFS performance, Dell recommends tuning the advanced NFS.MaxReadWriteSize parameter on the ESXi host to match the NAS server's preferred I/O size, which is typically much larger than 8k.

1. Dell PowerStore: VMware vSphere Best Practices (White Paper, April 2023):

For Correct Answer (C): Page 21, Section 4.2, "vVols with NFS". The document states, "For high availability, it is a best practice to create at least two NAS servers for vVols. Create one NAS server on each node of the PowerStore appliance."

For Incorrect Answer (D): Page 19, Section 3.3, "NFS datastores". This section discusses tuning the NFS.MaxReadWriteSize advanced parameter for best performance, contradicting the use of a small default size.

2. Dell PowerStore: Host Configuration Guide (Technical Document, June 2023):

For Incorrect Answer (A): Page 29, Section "VMware ESXi > Multipathing". The guide specifies, "For all PowerStore volumes presented to ESXi hosts, Dell recommends using the Round Robin multipathing policy with an I/O Operations limit of 1."

For Incorrect Answer (B): Page 33, Section "VMware ESXi > iSCSI configuration". The guide states, "To ensure optimal performance, disable the Delayed ACK setting on the ESXi host."