GRS provides a higher level of redundancy by replicating data across two Azure regions, which helps to ensure that backup data remains available in the event of a regional outage. However, this comes at a higher cost and may not always be necessary for all backup scenarios.
On the other hand, LRS provides a lower level of redundancy by replicating data within a single Azure region, which may be sufficient for some backup scenarios while being more cost-effective.
Therefore, moving Azure VM backup from GRS to LRS can help reduce backup costs while still maintaining an acceptable level of redundancy, depending on the business continuity requirements of the organization. It's important to assess the backup requirements of the organization and ensure that the chosen backup strategy aligns with those requirements to ensure adequate protection of critical data.
If a customer is charged for VMs backed up in the Recovery Services vault with GRS Redundancy, it affects the customer’s monthly budget. Moving the Recovery Services vault to LRS could be a solution. However, if we implement it directly, it will lose all the existing backed-up data.
By default, any Recovery services vault is configured in GRS. Running the Recovery Services vault in GRS will cost more Azure storage consumption. Moving data from GRS to LRS would save cost up to a reasonable extent, but there will be a loss of backed-up data during the transition.
Please follow the below steps to change from GRS to LRS and avoid data loss.
1. Azure VM backup with GRS redundancy with 7-14 copies of backup.
Backup flow diagram for the VM backup configured in GRS redundancy.
2. Disk snapshots of all the VMs get configured in Automation account and have 7-14 copies of backup before registering into LRS recovery services vault.
3. Servers are registered into the new backup vault with LRS redundancy with 7-14 copies of data.
Backup flow diagram would be same in LRS redundancy.
Technology Lead - Azure Infrastructure