Administrator 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.
Setting Up and Performing Disaster Recovery
This section contains a high-level overview of setting up and performing disaster recovery. In these instructions, Cluster A is the source
FluidFS cluster containing the data that must be backed up and Cluster B is the target FluidFS cluster, which backs up the data from
source cluster A.
Prerequisites
Prerequisites
• Cluster B is installed, but has no NAS volumes configured.
• Cluster A and Cluster B are at the same FluidFS version.
• Cluster B has different network settings (client, SAN, internal, and so on) than source Cluster A, however, Cluster A and Cluster B
must be able to communicate with each other so that replication operations can occur.
• Cluster B has enough space to replicate all data from Cluster A.
Phase 1 — Build up the replication partnership between Cluster A and Cluster B
Set up replication between Cluster A and Cluster B.
Steps
1. From Cluster A, set up a replication partnership between Cluster A and Cluster B.
2. Create a regular replication schedule so that the target volumes in Cluster B always have an up-to-date replication copy for Cluster A.
The replication policy must be a one-to-one match on a volume basis, for example:
Source volume A1 (Cluster A) to target volume B1 (Cluster B)
Source volume A2 (Cluster A) to target volume B2 (Cluster B)
NOTE:
If NFS exports are used, the NAS volume names of the source and target should be the same, as the export
path name includes the NAS volume name. This is not relevant for SMB shares.
Source volume An (Cluster A) to target volume Bn (Cluster B)
3. Ensure that at least one successful replication has occurred for all the source volumes in Cluster A.
If the replication fails, fix the problems encountered and restart the replication process.
4. Record all Cluster A settings for future use. Replication restore is not a complete BMR (bare metal restore). Settings such as network
configuration (client, SAN, and internal) cannot be backed up and restored using the replication method. Note all Cluster A settings
(for use when restoring Cluster A) including network configuration, cluster wide settings such as cluster name, alert settings, and so
on for future use. If the system restore operation fails to restore these settings, you can manually restore the Cluster A settings back
to their original values.
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FluidFS Administration