Purposes of SnapMirror

Why you want to replicate a volume

You want to replicate a volume if you are in any of the situations described in "When to copy volumes." Because SnapMirror offers additional advantages, there are other situations where you want to replicate a volume, as described in the following table.

Situation How data replication helps
Remote access to data
Users who need read access to a volume are distributed over a large geographical area.

You can replicate the source volume on other filers that are geographically closer to the users. Users accessing a local filer can read the data faster than they could if they connected to a distant filer.

Load balancing
A large number of users need only read access to a volume.

Replicating a volume on multiple filers enables you to distribute the load.

Backup
You need to reserve all processing and networking resources on a filer for serving NFS and CIFS requests.

After replicating data on the source filer, you can back up the data in the mirror to tape. This means the source filer does not have to allocate resources for performing backups.

Data migration
You want to migrate data from one filer to another without interrupting network service.

After replicating the source filer, you can export or share the source filer with read-only permissions so that network clients cannot make additional changes to the source filer. Because the source and destination filers contain identical data, you can change the status of each mirror on the destination filer to a regular volume. For more information about how to convert a mirror to a regular volume, refer to "Setting volume options."

Disaster recovery

You want to provide immediate access to data after some disaster has caused a volume or a filer to be unavailable.

You can change the status of the mirror to a regular volume. Users can immediately have access to the same data as that on the source volume. The snapmirrored volume option controls whether a volume is a mirror or a regular volume. For more information about volume options, refer to "Setting volume options."

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Part No. 210-02334
File: mirror1.htm
Last updated: 04/26/99 08:11:54