Explanation
You can upgrade or downgrade an ECS instance's configuration to meet your business needs. Upgrading an instance's configuration means increasing the vCPUs, memory, bandwidth, or disk capacity of the instance.
Downgrading an instance's configuration means decreasing the vCPUs, memory, bandwidth, or disk capacity of the instance. You can change the configuration of an ECS instance by using one of the following methods1:
Change the instance type: You can change the instance type of an ECS instance to adjust the vCPUs and memory of the instance. You can change the instance type of an ECS instance in the following scenarios2:
The instance is in the Stopped state and uses a pay-as-you-go billing method.
The instance is in the Running state and uses a subscription billing method, and the new instance type belongs to the same instance family as the original instance type.
Change the bandwidth configuration: You can change the bandwidth configuration of an ECS instance to adjust the network performance of the instance. You can change the bandwidth configuration of an ECS instance in the following scenarios3:
The instance is in the Stopped state and uses a pay-as-you-go billing method, and the instance is not associated with an EIP.
The instance is in the Running state and uses a subscription billing method, and the instance is not associated with an EIP.
Change the system disk or data disk: You can change the system disk or data disk of an ECS instance to adjust the disk capacity or performance of the instance. You can change the system disk or data disk of an ECS instance in the following scenarios4:
The instance is in the Stopped state and uses a pay-as-you-go billing method, and the disk is not encrypted.
The instance is in the Running state and uses a subscription billing method, and the disk is not encrypted. References: 1: Overview of instance configuration changes - Alibaba Cloud2: Change the instance type of an ECS instance - Alibaba Cloud3: Change the bandwidth configuration of an ECS instance - Alibaba Cloud4: Change the system disk or data disk of an ECS instance - Alibaba Cloud.