Your protection strategy should include plans for retaining the necessary local backups to meet your RPOs and RTOs. The most comprehensive strategy involves retaining recent local backups for quick recovery, and copying these backups to an offsite target for long-term retention and disaster recovery.
To create space for new backups, Unitrends appliances periodically purge older backups. You can use retention policies to control how long backups remain on the appliance. Backups held by a policy are never purged. An asset's latest backups are also never purged. New backups fail if an appliance cannot purge older backups to create sufficient space.
Retention settings assure that the necessary recovery points are available on your appliance. You create retention policies to hold backups for a specified number of days. You can create multiple policies and customize them to achieve different RPOs and RTOs for your assets. See Managing retention with long-term data management for details.
The amount of total backup storage capacity on the appliance varies by appliance type:
• | Recovery Series physical appliances come with a set amount of backup storage. You cannot add backup storage to the appliance. |
• | Unitrends Backup virtual appliances are deployed as virtual machines. During deployment, the initial backup storage was created using either a virtual attached disk, a SAN LUN, or a NAS share. After initial deployment, you can add more backup storage as desired. See About adding backup storage to a Unitrends Backup appliance for details. |
This storage capacity is used to store local backups, for VM instant recovery,and for Windows replicas. To use the instant recovery or Windows replicas features, you must reserve a portion of this storage to be used for instant recovery write space. For more on storage, see Backup storage.