This topic describes Alibaba Cloud regions and zones that you need to familiarize yourself with when you use networks.
Regions are geographical locations where Alibaba Cloud data centers are deployed. In most cases, regions are divided based on the cities where the data centers are deployed.
Zones are multiple, isolated locations within each region. Each zone has an independent power supply and network. Only zones in the same region can communicate with each other over the internal network. Resources that are deployed within the same zone share the same network and have minimal latency between each other. Therefore, services deployed within the same zone provide faster communication speeds, which translates into more efficient business operations. For more information about regions and zones, see Regions and zones.
Create instances in a zone
Before you create an Elastic Compute Service (ECS) instance, decide which region and zone best suit your business requirements. Resources in different regions are isolated from each other. When you view your resources, only the resources that are tied to the region that you specify are displayed. A region that is closer to the geographical location of your users provides lower latency and higher access speed.
Create a virtual private cloud (VPC) in the destination region. A VPC can be deployed in a region but cannot be deployed across regions. A VPC covers all zones of the region to which the VPC belongs. For more information, see IP addresses of ECS instances in VPCs.
Create a vSwitch to define a subnet in the destination zone. For more information, see Create and manage a vSwitch. Cloud resources cannot be directly deployed in a VPC, but must be deployed in vSwitches of a VPC. You can create one or more vSwitches in each zone.
- If your application requires high disaster recovery capabilities, we recommend that you deploy instances in different zones within the same region. If you distribute your instances across multiple zones and one instance fails, you can use an instance in another zone to handle requests.
- If your application requires low latency, we recommend that you deploy instances within the same zone.
Migrate instances to a different zone
You can migrate instances from one zone to another zone in the following scenarios: the instance type to which you want to upgrade is unavailable in the current zone, you want to obtain the cross-zone disaster recovery capability, and you want to reduce the latency when you call instances across zones.
- The software authorization codes of the instances are associated with media access control (MAC) addresses.
- You do not want to change the IDs of the instances and the disks because the IDs are used for business configurations.
- You do not want to be charged during migration.
- You do not want to change the public IP addresses of the instances because the public IP addresses are used for business configurations.