Dell FluidFS V3 NAS Solutions For PowerVault NX3500, NX3600, And NX3610Administrator's Guide

For single NAS volume failover, it is important that the environment is set up to properly migrate clients of the NAS volumes you are failing over, without disrupting the clients of other NAS volumes you are not failing over.

When a NAS Volume is failed over from one FluidFS cluster to another, the IP addresses that are used to access it change from Cluster A’s IP addresses to Cluster B’s IP addresses. Dell recommends facilitating this change using DNS. It is recommended to set up a DNS entry to correlate to each NAS volume, and change the DNS entry for single NAS volumes when they are failed over.

For example, suppose Marketing and Sales have their own NAS volumes, with a CIFS share on the NAS volume named marketing_share and sales_share respectively. A DNS entry named FluidFSmarketing, is created for Marketing and another DNS entry for Sales named FluidFSsales is created. Both NAS volumes point to the same set of client VIPs on source Cluster A. Marketing can access the Marketing NAS volume or CIFS share using

\\FluidFSmarketing\marketing, and Sales can access the Sales NAS volume or CIFS share using \\FluidFSsales\sales.

Initially, both DNS entries FluidFSmarketing and FluidFSsales point to the same set of client VIPs. At this point, both the marketing and sales CIFS shares can be accessed from either one of the DNS names, FluidFSmarketing or FluidFSsales. When you want to fail over a single NAS volume (for example Marketing) change the DNS entries for FluidFSmarketing to resolve to the client VIPs on Cluster B.

Dell recommends that you maintain a table to track which DNS entries are used to access each NAS volume. This helps when performing failover and setting up group policies.