Define a backup strategy for Exchange Server resources

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Defining a backup strategy before you create your backup jobs helps ensure that you have the backups that you require to successfully restore your databases. Your Service Level Agreement (SLA), Recovery Time Objective (RTO), and Recovery Point Objective (RPO) largely determine your backup strategy.

An SLA defines the level of service expected and addresses many service-related issues, including the availability and performance of service. The RTO is the time by when a business process must be restored after a disruption in service. An RPO defines the strategy for the age of the files that must be recovered from backup storage for regular operations to resume after a failure. The SLA, RTO, and RPO contribute to the backup strategy.

Types of backups supported for Exchange database

Backing up Exchange mailboxes using SnapCenter requires that you choose the resource type, such as databases and Database Availability Groups (DAG). Snapshot copy technology is leveraged to create online, read-only copies of the volumes on which the resources reside.

Backup type Description

Full and log backup

Backs up the databases and all transaction logs, including the truncated logs.

After a full backup is complete, the Exchange Server truncates the transaction logs that are already committed to the database.

Typically, you should choose this option. However, if your backup time is short, you can choose not to run a transaction log backup with full backup.

Full backup

Backs up databases and transaction logs.

The truncated transaction logs are not backed up.

Log backup

Backs up all the transaction logs.

The truncated logs that are already committed to the database are not backed up. If you schedule frequent transaction log backups between full database backups, you can choose granular recovery points.

Backup schedules for database plug-ins

Backup frequency (schedule type) is specified in policies; a backup schedule is specified in the resource group configuration. The most critical factor in determining a backup frequency or schedule is the rate of change for the resource and the importance of the data. You might back up a heavily used resource every hour, while you might back up a rarely used resource once a day. Other factors include the importance of the resource to your organization, your Service Level Agreement (SLA), and your Recover Point Objective (RPO).

An SLA defines the level of service expected and addresses many service-related issues, including the availability and performance of service. An RPO defines the strategy for the age of the files that must be recovered from backup storage for regular operations to resume after a failure. The SLA and RPO contribute to the data protection strategy.

Even for a heavily used resource, there is no requirement to run a full backup more than once or twice a day. For example, regular transaction log backups might be sufficient to ensure that you have the backups you need. The more often you back up your databases, the fewer transaction logs SnapCenter has to use at restore time, which can result in faster restore operations.

Backup schedules have two parts, as follows:

  • Backup frequency

    Backup frequency (how often backups are to be performed), called schedule type for some plug-ins, is part of a policy configuration. You can select hourly, daily, weekly, or monthly as the backup frequency for the policy. If you do not select any of these frequencies, then the policy created is an on-demand-only policy. You can access policies by clicking Settings > Policies.

  • Backup schedules

    Backup schedules (exactly when backups are to be performed) are part of a resource group configuration. For example, if you have a resource group that has a policy configured for weekly backups, you might configure the schedule to back up every Thursday at 10:00 PM. You can access resource group schedules by clicking Resources > Resource Groups.

Number of backup jobs needed for databases

Factors that determine the number of backup jobs that you need include the size of the resource, the number of volumes used, the rate of change of the resource, and your Service Level Agreement (SLA).

Backup naming conventions

You can either use the default Snapshot copy naming convention or use a customized naming convention. The default backup naming convention adds a timestamp to Snapshot copy names that helps you identify when the copies were created.

The Snapshot copy uses the following default naming convention:

resourcegroupname_hostname_timestamp

You should name your backup resource groups logically, as in the following example:

dts1_mach1x88_03-12-2015_23.17.26

In this example, the syntax elements have the following meanings:

  • dts1 is the resource group name.

  • mach1x88 is the host name.

  • 03-12-2015_23.17.26 is the date and timestamp.

Alternatively, you can specify the Snapshot copy name format while protecting resources or resource groups by selecting Use custom name format for Snapshot copy. For example, customtext_resourcegroup_policy_hostname or resourcegroup_hostname. By default, the time stamp suffix is added to the Snapshot copy name.

Backup retention options

You can choose either the number of days for which to retain backup copies or specify the number of backup copies you want to retain, up to a ONTAP maximum of 255 copies. For example, your organization might require that you retain 10 days of backup copies or 130 backup copies.

While creating a policy, you can specify the retention options for the backup type and the schedule type.

If you set up SnapMirror replication, the retention policy is mirrored on the destination volume.

SnapCenter deletes the retained backups that have retention labels that match the schedule type. If the schedule type was changed for the resource or resource group, backups with the old schedule type label might still remain on the system.

Note For long-term retention of backup copies, you should use SnapVault backup.

How long to retain transaction log backups on the source storage volume for Exchange Server

SnapCenter Plug-in for Microsoft Exchange Server needs transaction log backups to perform up-to-the-minute restore operations, which restore your database to a time between two full backups.

For example, if Plug-in for Exchange took a full plus transaction log backup at 8:00 a.m. and another full plus transaction log backup at 5:00 p.m., it could use the latest transaction log backup to restore the database to any time between 8:00 a.m. and 5:00 p.m. If transaction logs are not available, Plug-in for Exchange can perform point-in-time restore operations only, which restore a database to the time that Plug-in for Exchange completed a full backup.

Typically, you require up-to-the-minute restore operations for only a day or two. By default, SnapCenter retains a minimum of two days.