What Are Regions and AZs?

Regions and AZs

A region or an availability zone (AZ) identifies the location of a data center. You can create resources in a specific region or an AZ.

• A region is a geographic area where physical data centers are located. Each region is completely independent, improving the fault tolerance capability and stability. After a resource is created, its region cannot be changed.
• An AZ is a physical location with independent power supplies and network in a region. A region can contain multiple AZs, which are physically isolated but interconnected through internal networks. This ensures the independence of AZs and provides low-cost and low-latency network connections.

Figure 1 illustrates the relationship between regions and AZs.

Figure 1 Regions and AZs

Selecting a Region

You are advised to select a region close to you or your target users. This reduces network latency and improves access rate.

Selecting an AZ

When deploying resources, consider your applications' requirements on disaster recovery (DR) and network latency.

• For high DR capability, deploy resources in different AZs within the same region.
• If your applications require low latency between instances, you are advised to deploy resources in the same AZ.

Regions and Endpoints

Before using an API to call resources, you will need to specify the resource region and endpoint. For details, see "Endpoints" in Cloud Search Service API Reference.