Auto Scaling:Automatically bind EIPs to ECS instances

Procedure

You cannot specify EIPs when you create a scaling configuration. You can combine the lifecycle hook feature with an OOS template to automatically bind EIPs to ECS instances. This method is more efficient than manually binding EIPs to ECS instances after the ECS instances are created.

In this example, the ACS-ESS-LifeCycleAllocateEipAddressAndAttachToInstance OOS template is used as an example to bind EIPs to ECS instances during a scale-out. You must complete the following steps:

Step 1: Grant a RAM role the permissions on OOS

You must have the permissions to execute OOS templates. The O&M operations defined in the ACS-ESS-LifeCycleAllocateEipAddressAndAttachToInstance template are performed on resources such as ECS, Auto Scaling, and EIP resources.

1. Log on to the RAM console.

2. In the left-side navigation pane, choose Identities > Roles.

3. Find OOSServiceRole and click Grant Permission in the Actions column.

   Add the required permissions for the OOSServiceRole RAM role that is assumed by OOS to complete the authorization.

4. In the Grant Permission panel, configure parameters based on your business requirements and click OK.

   The following table describes the parameters that are used in this example. For parameters that are not described in the table, use the default settings.

   Parameter	Description
   Authorized Scope	Select Alibaba Cloud Account.
   Select Policy	Select the following system policies: AliyunECSFullAccess, AliyunESSFullAccess, and AliyunEIPFullAccess.

Step 2: Create a lifecycle hook of the scale-out type and trigger a scale-out

1. Log on to the Auto Scaling console.

2. In the left-side navigation pane, click Scaling Groups.

3. In the top navigation bar, select the region where Auto Scaling is activated.

4. Find a scaling group and use one of the following methods to go to the scaling group details page:

   • Click the ID of the scaling group in the Scaling Group Name/ID column.

   • Click Details in the Actions column.

5. Create a lifecycle hook of the scale-out type.

   1. In the upper part of the scaling group details page, click the Lifecycle Hook tab.

   2. Click Create Lifecycle Hook.

   3. Configure parameters based on your business requirements and click OK.

      The following table describes the parameters that are used in this example. For parameters that are not described in the table, use the default settings.

      Parameter	Description
      Name	Enter ESSHookForAttachEip.
      Scaling Activity	Select Scale-out Event.
      Timeout Period	Configure the Timeout Period parameter based on your business requirements. Unit: seconds. In this example, the Timeout Period parameter is set to 300. Note The timeout period is the period of time during which you can perform custom operations on ECS instances. If the timeout period is shorter than what is required to perform the custom operations, the operations may fail. We recommend that you assess the time required and configure the Timeout Period parameter based on your business requirements.
      Default Execution Policy	Select Continue.
      Send Notification When Lifecycle Hook Takes Effect	In this example, the following configurations are used: Select OOS Template. Select Public Templates. Select the ACS-ESS-LifeCycleAllocateEipAddressAndAttachToInstance public template. The following example shows how to configure execution parameters in the ACS-ESS-LifeCycleAllocateEipAddressAndAttachToInstance public template: internetChargeType: You can set the value to PayByBandwidth or PayByTraffic. If you set the value to PayByBandwidth, you are charged for the EIPs based on the bandwidth. If you set the value to PayByTraffic, you are charged for the EIPs based on the data transferred. In this example, PayByBandwidth is used. bandwidth: In this example, 5 is used. A value of 5 indicates that the peak bandwidth is 5 Mbit/s. eipTags: Add tags to the EIPs. You can manage your EIPs by group based on tags. OOSAssumeRole: Select OOSServiceRole. In Step 1, the OOSServiceRole RAM role obtains the permissions on ECS, Auto Scaling, and OOS resources. OOS can obtain the required permissions after it assumes the OOSServiceRole RAM role.

6. Trigger a scale-out.

   A scale-out is triggered in this example by manually executing a scaling rule. You can also trigger scale-outs by using scheduled or event-triggered tasks.

   Note

   If scaling activities are triggered when you manually execute scaling rules, lifecycle hooks take effect. Lifecycle hooks do not take effect when you manually add or remove ECS instances to or from a scaling group.

   1. In the upper part of the page that appears, click the Scaling Rules and Event-triggered Tasks tab.

   2. On the Scaling Rules tab, click Create Scaling Rule.

   3. In the Create Scaling Rule dialog box, configure parameters based on your business requirements and click OK.

      The following table describes the parameters that are used in this example. For parameters that are not described in the table, use the default settings.

      Parameter	Description
      Rule Name	Enter Add1.
      Rule Type	Select Simple Scaling Rule.
      Operation	Set the value to Add 1 Instances.

   4. On the Scaling Rules tab, find the Add1 scaling rule and click Execute in the Actions column.

   5. In the message that appears, click OK.

   After the Add1 scaling rule is executed, one ECS instance is created. Due to the ESSHookForAttachEip lifecycle hook, the ECS instance enters the Pending Add state, and Auto Scaling notifies OOS to execute the O&M operations defined in the ACS-ESS-LifeCycleAllocateEipAddressAndAttachToInstance template.

   If the scale-out failed and the following error is reported, you can go to the OSS console to check the execution of the O&M operations. For more information, see (Optional) Step 3: View the OOS execution.

7. Check whether the automatically created ECS instance meets your expectations.

   1. In the upper part of the scaling group details page, click the Instances tab.

   2. Find the automatically created ECS instance and click its ID in the ECS Instance ID/Name section.

   3. In the left-side navigation pane of the page that appears, click the Instance Details tab.

      If the output is similar to the following figure, an EIP is bound to the ECS instance, which specifies that the ACS-ESS-LifeCycleAllocateEipAddressAndAttachToInstance public template yields the expected effect.

      If the ECS instance is created but no EIP is bound, you can go to the OOS console to check the execution of the O&M operations. For more information, see (Optional) Step 3: View the OOS execution.

(Optional) Step 3: View the OOS execution

1. Log on to the OOS console.

2. In the left-side navigation pane, choose Automated Tasks > Task Execution Management.

3. Filter O&M tasks by start time and click Details in the Actions column of the desired O&M task.

4. On the execution details page, view information about the task.

   For example, in the Basic Information section, you can view the execution ID and status. In the Execution Steps and Results section, you can click a task node to view the execution details. For more information, see View the details of an execution.

   Important

   If the task failed, the error message is displayed on the execution details page.

FAQ

References

• When you create a scaling configuration, you cannot specify secondary ENIs or EIPs. If you want to specify EIPs for ECS instances, you can combine the lifecycle hook feature with OOS templates to automatically bind secondary ENIs that have EIPs. Automatic EIP binding is more efficient than manual binding after ECS instances are created. For more information, see Automatically bind secondary ENIs to ECS instances.

• You can also combine the lifecycle hook feature of Auto Scaling with OOS to implement automatic release of EIPs or automatic unbinding of secondary ENIs that provide the EIPs from ECS instances. For more information, see the following links:

  • Automatically release EIPs of ECS instances

  • Automatically unbind secondary ENIs from ECS instances