Regions and Availability Zones

Last updated: 2021-08-12 17:18:20

    Regions

    Overview

    A region is the physical location of an IDC. In Tencent Cloud, regions are fully isolated from each other, ensuring cross-region stability and fault tolerance. We recommend that you choose the region closest to your end users to minimize access latency and improve access speed.

    You can view the following table or use the DescribeRegions API to get a complete list region list.

    Characteristics

    • The networks of different regions are fully isolated. Tencent Cloud services in different regions cannot communicate via a private network by default.
    • Tencent Cloud services across regions can communicate with each other through public IPs over the Internet, while those in different VPCs can communicate with each other through CCN, which is faster and more stable.
    • Cloud Load Balancer currently supports intra-region traffic forwarding by default. If you enable the cross-region binding feature, a CLB instance can be bound to CVM instances in another region.

    Availability Zones

    Overview

    An availability zone (AZ) is a physical IDC of Tencent Cloud with independent power supply and network in the same region. It can ensure business stability, as failures (except for major disasters or power failures) in one AZ are isolated without affecting other AZs in the same region. By starting an instance in an independent availability zone, users can protect their applications from being affected by a single point of failure.
    You can view the following table or use the DescribeZones API to get a complete availability zone list.

    Characteristics

    Tencent Cloud services in the same VPC are interconnected via the private network, which means they can communicate using private IPs, even if they are in different availability zones of the same region.

    Note:

    Private network interconnection refers to the interconnection of resources under the same account. Resources under different accounts are completely isolated on the private network.

    China

    Region AZ
    South China (Guangzhou)
    ap-guangzhou
    Guangzhou Zone 1 (sold out)
    ap-guangzhou-1
    Guangzhou Zone 2 (sold out)
    ap-guangzhou-2
    Guangzhou Zone 3
    ap-guangzhou-3
    Guangzhou Zone 4
    ap-guangzhou-4
    Guangzhou Zone 6
    ap-guangzhou-6
    Guangzhou Zone 7
    ap-guangzhou-7
    East China (Shanghai)
    ap-shanghai
    Shanghai Zone 1
    ap-shanghai-1
    Shanghai Zone 2
    ap-shanghai-2
    Shanghai Zone 3
    ap-shanghai-3
    Shanghai Zone 4
    ap-shanghai-4
    Shanghai Zone 5
    ap-shanghai-5
    East China (Nanjing)
    ap-nanjing
    Nanjing Zone 1
    ap-nanjing-1
    Nanjing Zone 2
    ap-nanjing-2
    Nanjing Zone 3
    ap-nanjing-3
    North China (Beijing)
    ap-beijing
    Beijing Zone 1
    ap-beijing-1
    Beijing Zone 2
    ap-beijing-2
    Beijing Zone 3
    ap-beijing-3
    Beijing Zone 4
    ap-beijing-4
    Beijing Zone 5
    ap-beijing-5
    Beijing Zone 6
    ap-beijing-6
    Beijing Zone 7
    ap-beijing-7
    Southwest China (Chengdu)
    ap-chengdu
    Chengdu Zone 1
    ap-chengdu-1
    Chengdu Zone 2
    ap-chengdu-2
    Southwest China (Chongqing)
    ap-chongqing
    Chongqing Zone 1
    ap-chongqing-1
    Hong Kong, Macao and Taiwan, China (Hong Kong)
    ap-hongkong
    Hong Kong Zone 1 (Nodes in Hong Kong, China can cover Hong Kong/Macao/Taiwan regions)
    ap-hongkong-1
    Hong Kong Zone 2 (Nodes in Hong Kong, China can cover Hong Kong/Macao/Taiwan regions)
    ap-hongkong-2
    Hong Kong Zone 3 (Nodes in Hong Kong, China can cover Hong Kong/Macao/Taiwan regions)
    ap-hongkong-3

    Other Countries and Regions

    Region AZ
    Southeast Asia (Singapore)
    ap-singapore
    Singapore Zone 1 (Nodes in Singapore can cover Southeast Asia)
    ap-singapore-1
    Singapore Zone 2 (Nodes in Singapore can cover Southeast Asia)
    ap-singapore-2
    Singapore Zone 3 (Nodes in Singapore can cover Southeast Asia)
    ap-singapore-3
    Southeast Asia (Jakarta)
    ap-jakarta
    Jakarta Zone 1 (Nodes in Jakarta can cover Southeast Asia)
    ap-jakarta-1
    Northeast Asia (Seoul)
    ap-seoul
    Seoul Zone 1 (Nodes in Seoul can cover Northeast Asia)
    ap-seoul-1
    Seoul Zone 2 (Nodes in Seoul can cover Northeast Asia)
    ap-seoul-2
    Northeast Asia (Tokyo)
    ap-tokyo
    Tokyo Zone 1 (Nodes in Tokyo can cover Northeast Asia)
    ap-tokyo-1
    Tokyo Zone 2 (Nodes in Tokyo can cover Northeast Asia)
    ap-tokyo-2
    South Asia (Mumbai)
    ap-mumbai
    Mumbai Zone 1 (Nodes in Mumbai can cover South Asia)
    ap-mumbai-1
    Mumbai Zone 2 (Nodes in Mumbai can cover South Asia)
    ap-mumbai-2
    Southeast Asia (Bangkok)
    ap-bangkok
    Bangkok Zone 1 (Nodes in Bangkok can cover Southeast Asia)
    ap-bangkok-1
    Bangkok Zone 2 (Nodes in Bangkok can cover Southeast Asia)
    ap-bangkok-2
    North America (Toronto)
    na-toronto
    Toronto Zone 1 (Nodes in Toronto can cover North America)
    na-toronto-1
    Western US (Silicon Valley)
    na-siliconvalley
    Silicon Valley Zone 1 (Nodes in Silicon Valley can cover Western US)
    na-siliconvalley-1
    Silicon Valley Zone 2 (Nodes in Silicon Valley can cover Western US)
    na-siliconvalley-2
    Eastern US (Virginia)
    na-ashburn
    Virginia Zone 1 (Nodes in Virginia can cover Eastern US)
    na-ashburn-1
    Virginia Zone 2 (Nodes in Virginia can cover Eastern US)
    na-ashburn-2
    Europe (Frankfurt)
    eu-frankfurt
    Frankfurt Zone 1 (Nodes in Frankfurt can cover Europe)
    eu-frankfurt-1
    Frankfurt Zone 2 (Nodes in Frankfurt can cover Europe)
    eu-frankfurt-2
    Europe (Moscow)
    eu-moscow
    Moscow Zone 1 (Nodes in Moscow can cover Europe)
    eu-moscow-1

    How to Select Regions and Availability Zones

    When selecting a region and availability zone, take the following into consideration:

    • Your location, the location of your users, and the region of the CVM instances.
      We recommend that you choose the region closest to your end users when purchasing CVM instances to minimize access latency and improve access speed.
    • Other Tencent Cloud services you use.
      When you select other Tencent Cloud services, we recommend you try to locate them all in the same region and availability zone to allow them to communicate with each other through the private network, reducing access latency and increasing access speed.
    • High availability and disaster recovery.
      Even if you have just one VPC, we still recommend that you deploy your businesses in different availability zones to prevent a single point of failure and enable cross-AZ disaster recovery.
    • There may be network latency among different availability zones. We recommend that you assess your business requirements and find the optimal balance between high availability and low latency.
    • If you need access to CVM instances in other countries or regions, we recommend you select a CVM in those other countries or regions. If you use a CVM instance in China to access servers in other countries and regions, you may encounter much higher network latency.

    Resource Availability

    The following table describes which Tencent Cloud resources are global, which are regional, and which are specific to availability zones.

    ResourceResource ID Format
    -8-Digit String of Numbers and Letters
    TypeDescription
    User Account No limit Globally unique Users can use the same account to access Tencent Cloud resources around the world.
    SSH Keys skey-xxxxxxxx Global Users can use an SSH key to bind a CVM in any region under the account.
    CVM Instances ins-xxxxxxxx CVM instances are specific to an availability zone A CVM instance created in an availability zone is not available to other availability zones.
    Custom Images img-xxxxxxxx Regional Custom images created for the instance are available to all availability zones of the same region. Use Copy Image to copy a custom image if you need to use it in other regions.
    EIPs eip-xxxxxxxx Regional EIPs can only be associated with instances in the same region.
    Security Groups sg-xxxxxxxx Regional Security group can only be associated with instances in the same region. Tencent Cloud automatically creates three default security groups for users.
    Cloud Block Storage disk-xxxxxxxx CBS disks are specific to an availability zone. Users can only create a Cloud Block Storage disk in a specific AZ and mount it to instances in the same availability zone.
    Snapshots snap-xxxxxxxx Regional A snapshot created from a cloud disk can be used for other purposes (such as creating cloud disks) in this region.
    Cloud Load Balancer clb-xxxxxxxx Regional Cloud Load Balancer can be bound with CVMs in different availability zones of a single region for traffic forwarding.
    VPC vpc-xxxxxxxx Regional A VPC in one region can have resources created in different availability zones of the region.
    Subnets subnet-xxxxxxxx Subnets are specific to an availability zone. Users cannot create subnets across availability zones.
    Route Tables rtb-xxxxxxxx Regional When creating a route table, users need to specify a VPC. Therefore, route tables are regional as well.

    Relevant Operations

    Migrating an instance to another availability zone

    Once launched, an instance cannot be migrated. However, you can create a custom image of your CVM instance and use the image to launch or update an instance in a different availability zone.

    1. Create a custom image from the current instance. For more information, see Creating Custom Images.
    2. If the instance is on a VPC and you want to retain its current private IP address after the migration, first delete the subnet in the current availability zone and then create a subnet in the new availability zone with the same IP address range. Note that a subnet can be deleted only when it contains no available instances. Therefore, all the instances in the current subnet should be migrated to the new subnet.
    3. Create a new instance in the new availability zone by using the custom image you have just created. You can choose the same type and configuration as the original instance, or choose new settings. For more information, see Creating Instances via CVM Purchase Page.
    4. If an elastic IP is associated with the original instance, dissociate it from the old instance and associate it with the new instance. For more information, see Elastic IP (EIP).
    5. (Optional) If the original instance is pay-as-you-go, you can choose to terminate it. For more information, see Terminating Instances.

    Copying images to other regions

    Operations such as launching and viewing instances are region-specific. If the image of the instance that you need to launch does not exist in the region, copy the image to the desired region. For more information, see Copying Images.