Server Migration Center (SMC) allows you to migrate Elastic Compute Service (ECS) instances across zones in a specific region. This improves the efficiency of migrating ECS instances on Alibaba Cloud. This topic describes the benefits, scenarios, and limits of the cross-zone migration feature.
Benefits
High migration efficiency
You can migrate multiple ECS instances across zones at a time to improve migration efficiency.
Cost-effectiveness
You do not need to purchase new ECS instances in other zones. This reduces costs.
Seamless upgrade
You can upgrade the configurations of ECS instances and migrate them across zones at the same time.
Simple and convenient operations
You can complete a cross-zone migration task with simple operations.
Scenarios
Change the zone of ECS instances.
The instance type resources of ECS instances are insufficient in the current zone. You want to change the instance types of the instances to a specific instance type in a different zone within the same region.
You want to migrate ECS instances to another zone within the same region based on your business requirements.
Change the types of ECS instances.
You want to change the types of ECS instances because the current instance types cannot meet your business requirements.
Migration process
The following figure shows the process of migrating an ECS instance across zones.
Limits
The following instance families do not support cross-zone instance type changes:
Heterogeneous computing instance families
ECS Bare Metal Instance families
Super Computing Cluster (SCC) instance families
General-purpose computing u1 instance family
Instance families based on the x86 architecture:
Big data instance families
Instance families with local SSDs
Security-enhanced instance families
For more information about instance families, see Overview of instance families.
You can change an instance type only into another type within the same instance family.