TencentDB data centers are hosted in multiple locations worldwide. These locations are known as regions. Each region contains multiple availability zones (AZs).
Each region is an independent geographic area containing multiple isolated AZs. Separate AZs in the same region are connected via low-latency private networks. Tencent Cloud provides you with the ability to distribute Tencent Cloud resources across different locations. We recommend placing resources in different AZs to eliminate single points of failure which may lead to service unavailability.

Region name and AZ name can most directly embody the coverage of a data center. The following naming convention is used for your convenience:

• A region name is composed of region + city. The region indicates the geographic area that the data center covers, while the city represents the city in or near which the data center is located.
• AZ names utilizes the format of city + number.

Region

Tencent Cloud regions are completely isolated. This guarantees the maximum cross-region stability and fault tolerance. When purchasing Tencent Cloud services, we recommend selecting the region closest to your end users to minimize access latency and improve download speed. Operations such as launching or viewing instances are performed at the region level.
Private Network Communication:

• Tencent Cloud resources in different AZs within the same region can communicate with each other over private network. They can also be accessed via private IPs.
• Tencent Cloud products in different regions cannot communicate with each other over the private network by default.
  • By default, CVM instances cannot communicate with each other over the private network across regions or access TencentDB or Cloud Memcached across regions.
  • When a CVM instance is bound to a CLB instance, only the instances in the same region can be selected.
• Tencent Cloud resources in different regions can be accessed over the Internet through public IPs. Tencent Cloud services in VPCs can communicate with each other over Tencent Cloud high-speed network via peering connections, which is more stable and faster than public Internet.
• CLB does not support cross-region traffic forwarding.

The above notes regarding private network communication only applies to resources under the same account. Resources under different accounts are completely isolated.

Availability Zone

Availability zones (AZs) refer to Tencent Cloud's physical data centers that are in the same region. Each AZ is independently powered and have its own network resources. They are designed to ensure that failures within one AZ can be isolated from other zones, thereby ensuring service availability and business stability, excepting the occurrences of large-scale disasters or major power failures. Users can protect their applications from being affected by failures that occur in a single location by selecting instances in independent AZs.
When launching an instance, you can select any AZ in the specified region. For high reliability, you can adopt a cross-AZ deployment solution to ensure that the service remains available when an instance in a single location fails. Examples of such solutions include CLB and EIP.

List of Regions and AZs

Regions and AZs:

China

Other Countries/Regions

Selecting Regions and AZs

When purchasing Tencent Cloud services, we recommend selecting the region closest to your end users to minimize access latency and improve download speed.