Dell Storage Manager 2020 R1 Administrator's Guide

Managing the DNS Configuration for Single NAS Volume Failover

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. You can facilitate 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, each with an SMB share on the NAS volumes 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 SMB share using \\FluidFS marketing\marketing, and Sales can access the Sales NAS volume or SMB share using \\FluidFSsales\sales.

Initially, both DNS entries FluidFSmarketing and FluidFS sales point to the same set of client VIPs. At this point, both the marketing and sales SMB shares can be accessed from either one of the DNS names, FluidFSmarketing or FluidFS sales. 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.

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.