Geo Zone Redundant Storage (GZRS) is now available for additional Azure SQL database service tiers

Summary:

Great news! Geo Zone Redundant Storage (GZRS) is now available for service tiers such as Standard, Premium, General Purpose, and Business Critical. This means more flexibility and enhanced data and backup protection for more service tiers.

Details:

When it comes to resiliency of a business-critical database, backups are as critical as the source data itself in the event of any disruption. In Azure SQL, Geo Zone Redundant Storage (GZRS) offers the highest level of protection against zonal outages as well as regional outages for any workload.  

Today when you deploy a Business Critical or General Purpose SKU of Azure SQL database, the following are the options you get for your backup storage redundancy: 

Below is a screenshot with current backup storage redundancy options for a Business Critical service tier: 

Choosing the right storage type for SQL Database backups depends on your specific needs for availability, and cost. Locally Redundant Storage (LRS) is cost-effective for less critical data, while Zone Redundant Storage (ZRS), Geo Redundant Storage (GRS), and Geo-Zone Redundant Storage (GZRS) offer increasing levels of protection and availability for more sensitive applications. 

Here’s a brief description of each of these storage types: 

1. Locally Redundant Storage (LRS)
   • Replication: LRS replicates data three times within a single data center in the primary region. 
   • Durability: Offers at least 99.999999999% durability over a year.  
   • Use Case: Ideal for non-critical data where cost is a primary concern. However, it does not protect against regional disasters. 

1. Zone-Redundant Storage (ZRS)
   • Replication: ZRS replicates data across three separate Azure availability zones within the primary region. 
   • Durability: Provides a higher durability of 99.9999999999% (12 nines) over a year. 
   • Use Case: Suitable for applications requiring high availability and resilience against zone failures, ensuring data remains accessible even if one zone goes down. 

1. Geo-Redundant Storage (GRS)
   • Replication: GRS combines LRS with geo-replication, storing three copies in the primary region and three additional copies in a paired secondary region. 
   • Durability: Offers the same durability as LRS in the primary region, but with added protection from regional disasters. 
   • Use Case: Best for critical data that requires disaster recovery capabilities, though the secondary region is not accessible for reads until a failover occurs. 

1. Geo-Zone Redundant Storage (GZRS)
   • Replication: GZRS combines ZRS with geo-replication storing three copies in the primary region that are zone-redundant and three additional copies in a paired secondary region. 
   • Durability: Provides the durability benefits of ZRS along with the geo-redundancy of GRS. 
   • Use Case: Ideal for mission-critical applications needing both high availability and disaster recovery, ensuring data is protected against both zone and regional failures. 

If you think about this from the context of database backups: 

• with LRS – the backups are redundant within the zone. If there is an outage in the data center, despite having multiple copies of the backups, the backups are not accessible until the data center comes back online.  

• With ZRS – storage replicates the backups across the zones. If there is an outage in the zone, then backups are available in one of the other zones within the region. 

• With GRS – the backups are redundant across geographic regions. However, within the region they are stored in LRS storage. While you get geo-redundancy your regional resiliency story has the same downside that comes with LRS. 

• With GZRS – the backups are redundant within the region and across geographic regions. This offers the highest level of redundancy and protection from failures. If there is an outage within the zone, backups are available in one of the other zones within the region. If the entire region is unavailable, backups are available in the geo-paired region. 

Until today, LRS, ZRS and GRS were the only options available for non-Hyperscale database service tiers such as Standard, Premium, General Purpose and Business Critical.

We are thrilled to announce that GZRS storage that provides the highest level of durability and resiliency, is now available for Standard, Premium, General Purpose and Business Critical as well. 

Below is a screenshot with updated backup storage redundancy options for Business Critical service tier: 

Tip: It is highly recommended to align the redundancy of your data and backups.

For instance, if your database is zone redundant, you want your backups also to be zone redundant and either ZRS or GZRS. If you configure your database to be redundant but leave your backups in LRS then, in the event of an outage in the primary zone, your database fails over to another zone within the region because you configured it to be zone redundant. However, since your backups are in LRS, your backups are not available or accessible from another zone within the region. This could result in disruption as your primary database now cannot be backed up until the zone that had the outage is back online.  

Note: The GZRS storage type for Hyperscale SKU is already available today. 

Note: There is another announcement about price adjustment (read reduced!) to Backup storage redundancy pricing for all storage types across all Azure SQL DB and Azure SQL MI. More details here - Simplified & lower pricing for Azure SQL Database and Azure SQL Managed Instance backup storage