A scaling group is a collection of ECS instances with similar configuration deployed in an application scenario.
It defines the maximum and minimum number of ECS instances in the group, associated Server Load Balancer and RDS instances, and other attributes.
- Log on to the Auto Scaling console.
- On the Scaling Groupspage, click Create Scaling Group.
- Set the scaling group parameters, and click Submit.
Note For scaling group attributes, see create a scaling group.
- Click Create Scaling Configuration.
Note For more information about scaling configuration, see create a scaling configuration.
- In the Enable Scaling Group dialog box, click OK.
Scaling group attributes
The following table lists the specific scaling group attribute meanings and examples.
|Scaling group name||The name consists of 2-40 characters. It must begin with a lower-case letter, number, or a Chinese character, and can contain ".", "_" or "-".||sg-yk201808201449||Yes|
|Maximum number of instances for scaling||Maximum number of ECS instances in the scaling group When the upper limit is exceeded, Auto Scaling removes the ECS instances automatically based on the removal policy to make the current number of ECS instances equal to the upper limit.||10||Yes|
|Minimum number of instances for scaling||Minimum number of ECS instances in the scaling group When the lower limit is exceeded, Auto Scaling adds the ECS instances automatically to make the current number of ECS instances equal to the lower limit.||1||Yes|
|Default cool-down time (second)||The default cool-down time after a scaling activity occurs in the scaling group For more information, see cool-down time.||600||Yes|
|Removal policy||The policy to remove the ECS instances when the number of ECS instances in the scaling group exceeds the upper limit For more information, see removal policy.||The instance corresponded to the oldest scaling configuration||Yes|
|Network type||The type of network to which the scaling group belongs You can select Classic Network or VPC. If you select VPC, you must configure multiple VSwitches. Select multi-zone scaling policies and recycling modes as needed. For specific parameters, see multi-zone scaling policies and recycling modes.||VPC||Yes|
|Server Load Balancer||If a Server Load Balancer instance is added when you create a scaling group, the scaling group automatically adds the ECS instances in the group to the Server Load Balancer instance. The Server Load Balancer instance in a scaling group extends the service capability of the application and enhances the availability of the application.||slb-yk201807061512||No|
|Database||If an RDS instance is added when you create a scaling group, the scaling group automatically adds the intranet IP of the ECS instance that joined the scaling group to the whitelist of the specified RDS, allowing intranet communication between the ECS instances.||5.7 Basic Edition||No|
Multi-zone scaling policy
|Priority policy||Perform scaling according to the VSwitch you define. When ECS instances cannot be created in the zone to which the VSwitch with higher priority belongs, the system automatically uses the VSwitch with the next priority to create the ECS instance.|
|Even distribution policy||Evenly allocates ECS instances to multiple zones (that is, multiple VSwitches specified) specified by the scaling group. If the distribution becomes disequilibrium, you can re-allocate the instances to zones.
Note When you set multiple VSwitches, the policy takes effect.
|Cost optimization policy||The network type of the scaling group is VPC:
|Release mode||During scaling down, proper number of ECS instances are automatically released based on the scheduled or alarm tasks.
During scaling up, proper number of ECS instances are created to join the scaling group based on the scheduled or alarm tasks.
|Downtime recycling mode||The downtime recycling mode improves the time efficiency of scaling. In this mode: