Disaster recovery plans often require that you back up and replicate the same VM for DR and HA purposes. Normally, this doubles the workload on the virtual infrastructure. You need to create two VM snapshots, independently from one another, and transfer VM data from the production site twice.
You can reduce the workload on the production environment by using the replica from backup option. This option can be used for onsite and offsite replication scenarios.
When you perform replication from backup, Veeam Backup & Replication does not address hosts and storage in the production environment to read VM data. As a source of data, it uses a backup chain that already exists on the backup repository. As a result, you do not need to create a VM snapshot for replication and transport the same data twice. You retrieve VM data only during the backup job. The replication job re-uses retrieved data to build VM replica restore points.
Although replica from backup might resemble replica seeding, there is difference between these options:
- Replica seeding uses the backup file only during the first run of a replication job. To further build VM replica restore points, the replication job addresses the production environment and reads VM data from the source storage.
- Replica from backup uses a backup chain on the backup repository as the only source of data. When building a new VM replica restore point, Veeam Backup & Replication always reads data from the latest restore point in the backup chain, either full or incremental. The backup chain on the backup repository may be created with a backup job or a backup copy job.
Limitations for Replica from Backup
- You can perform replication only from backups of VMware vSphere virtual machines created with Veeam Backup & Replication. Replication from backups of vCloud Director virtual machines is not supported.
- A backup that you plan to use for replication must be mapped to a backup job on the backup server where you configure the replication job.
If you want to use a backup created on another backup server, perform the following steps:
- Import the backup to the Veeam Backup & Replication console.
- Create a new backup job and map the imported backup to it.
- Create a replication job, enable the Get seed from the following backup repository option and point to the backup repository where the imported backup resides.
Mind the following:
- The backup job to which you map the imported backup file on another backup server must run periodically and produce new restore points. You cannot create a job, map the imported backup to it and never run this job.
- No other job on any other backup server must use the imported backup.