Merge pull request #291050 from anaharris-ms/reliability-non-zonal-description

Reliability - Add explicit statement about non-zonal/regional services

Author: prmerger-automator[bot]

articles/reliability/availability-zones-overview.md

@@ -39,8 +39,9 @@ There are two ways that Azure services use availability zones:
 
 Azure services support one or both of these approaches. Platform as a service (PaaS) services typically support zone-redundant deployments. Infrastructure as a service (IaaS) services typically support zonal deployments. For more information about how Azure services work with availability zones, see [Azure regions with availability zone support](availability-zones-region-support.md).
 
-For information on service-specific reliability support using availability zones as well as recommended disaster recovery guidance see [Reliability guidance overview](./reliability-guidance-overview.md).
+Some services don't use availability zones until you configure them to do so. If you don't explicitly configure a service for availability zone support, it's called a *non-zonal* or *regional* deployment. Resources configured in this way might be placed in any availability zone in the region, and might be moved. If any availability zone in the region experiences an outage, non-zonal resources might be in the affected zone and could experience downtime.
 
+For information on service-specific reliability support using availability zones as well as recommended disaster recovery guidance see [Reliability guidance overview](./reliability-guidance-overview.md).
 
 ## Physical and logical availability zones
 

articles/reliability/availability-zones-service-support.md

@@ -20,12 +20,14 @@ Azure is continually expanding the number of services that support availability
 
 ## Types of availability zone support
 
-Azure services can provide two types of availability zone support: *zonal* and *zone-redundant*. Each service supports either one or both types. When designing your reliability strategy, make sure that you understand which availability zone types are supported in each service of your workload. 
+Azure services can provide two types of availability zone support: *zonal* and *zone-redundant*. Each service might support one or both types. When designing your reliability strategy, make sure that you understand which availability zone types are supported in each service of your workload. 
 
 - **Zonal services**: A resource can be deployed to a specific, self-selected availability zone to achieve more stringent latency or performance requirements. Resiliency is self-architected by replicating applications and data to one or more zones within the region. Resources are aligned to a selected zone. For example, virtual machines, managed disks, or standard IP addresses can be aligned to a same zone, which allows for increased resiliency by having multiple instances of resources deployed to different zones.
 
 - **Zone-redundant services**: Resources are replicated or distributed across zones automatically. For example, zone-redundant services replicate the data across multiple zones so that a failure in one zone doesn't affect the high availability of the data. 
 
+Some services don't use availability zones until you configure them to do so. If you don't explicitly configure a service for availability zone support, it's called a *non-zonal* or *regional* deployment. Resources configured in this way might be placed in any availability zone in the region, and might be moved. If any availability zone in the region experiences an outage, non-zonal resources might be in the affected zone and could experience downtime.
+
 >[!IMPORTANT]
 >Some services may have limited support for availability zones. For example, some may only support availability zones for certain tiers, regions, or SKUs. To get more information on service limitations for availability zone support, select that service in the table.