Zone-redundant storage: data is written three times, each copy in a different availability zone of the same region, and nothing is replicated to a secondary region.
Also called zone-redundant storage.
Read more: Microsoft Learn
In the Ultra Transcenders books
AZ-305AZ-104AZ-900DP-900AZ-802
Each book explains ZRS in context, with comparison tables and the common traps.
Terms in this definition
- Availability zone
One or more datacentres in an Azure region that are physically apart from the rest and have their own power, cooling and network. If one zone fails, the others keep running.
- region
A provider-defined grouping in VCF Automation of Supervisors that all share one NSX Local Manager; tenants consume its compute, storage and memory via quotas set per region.
- 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.
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.
- Backup storage redundancy
Replication choice for a Recovery Services vault (GRS unless you pick LRS or ZRS). Set it before protecting the first item, because it is locked once backup has been configured.
- BlockBlobStorage
Premium, SSD-backed account kind dedicated to block and append blobs, giving the lowest latency; redundancy is limited to LRS or ZRS and access tiers aren't available.
- FileStorage
Storage account kind on premium SSD dedicated to Azure Files, supporting only ZRS or LRS redundancy.
- General-purpose v1
The older storage account kind (
Storage), which lacks access tiers, Archive and premium file shares and retires on 13 October 2026. Converting to ZRS requires first upgrading to GPv2, a one-way change. - 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.
- Managed disks
Block storage disks for VMs whose underlying storage accounts Azure looks after. The only redundancy choices are LRS and ZRS.
- Premium Azure Files
File shares on FileStorage accounts backed by SSDs, giving latency in single-digit milliseconds for transaction-heavy work. Only LRS and ZRS are offered, so geo-redundancy is unavailable.