Geo-zone-redundant storage that also lets you read the secondary region's copy at any time, with no failover required. Microsoft suggests it where the highest availability and durability are wanted.
Also called read-access geo-zone-redundant storage.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains RA-GZRS in context, with comparison tables and the common traps.
Terms in this definition
- GZRS
Geo-zone-redundant storage. Writes go synchronously to at least three availability zones in the primary region, as ZRS does, and are later copied asynchronously to a secondary region that keeps LRS copies. With RA-GZRS that secondary can also be read.
- CRUD
Shorthand for create, read, update and delete, the four basic things you do with data. Data-plane roles in Azure Cosmos DB, for instance, authorise those operations on items.
- Secondary region
Holds disaster-recovery copies of data or workloads, typically hundreds of miles away from the primary location. Geo-redundant storage always uses the primary's pair for this, with no option to change it.
- WHERE
Limits a SELECT, UPDATE or DELETE to just the rows meeting a condition. Omit it, and the statement hits every row.
- ACID
Four promises a database transaction makes: atomicity, consistency, isolation and durability. Azure Cosmos DB honours them, with snapshot isolation, only inside one logical partition, using stored procedures, triggers or transactional batch.
Related terms
- Archive tier
An offline blob access tier offering the cheapest storage, meant for data that is hardly ever read. Archived blobs must first be rehydrated to the Hot, Cool or Cold tier, which may take as long as 15 hours, before you can read or change them, and ZRS, GZRS and RA-GZRS accounts can't use this tier.