Register targets with your target group - Elastic Load Balancing

Register targets with your target group

When your target is ready to handle requests, you register it with one or more target groups. You can register targets by instance ID or by IP address. The Gateway Load Balancer starts routing requests to the target as soon as the registration process completes and the target passes the initial health checks. It can take a few minutes for the registration process to complete and health checks to start. For more information, see Health checks for your target groups.

If demand on your currently registered targets increases, you can register additional targets in order to handle the demand. If demand on your registered targets decreases, you can deregister targets from your target group. It can take a few minutes for the deregistration process to complete and for the Gateway Load Balancer to stop routing requests to the target. If demand increases subsequently, you can register targets that you deregistered with the target group again. If you need to service a target, you can deregister it and then register it again when servicing is complete.

When you deregister a target, Elastic Load Balancing waits until in-flight requests have completed. This is known as connection draining. The status of a target is draining while connection draining is in progress. After deregistration is complete, status of the target changes to unused. For more information, see Deregistration delay.

Target security groups

When you register EC2 instances as targets, you must ensure that the security groups for these instances allow traffic on port 6081.

Gateway Load Balancers do not have associated security groups. Therefore, the security groups for your targets must use IP addresses to allow traffic from the load balancer.

Network ACLs

When you register EC2 instances as targets, you must ensure that the network access control lists (ACL) for the subnets for your instances allow traffic on port 6081. The default network ACL for a VPC allows all inbound and outbound traffic. If you create custom network ACLs, verify that they allow the appropriate traffic.

Register or deregister targets

Each target group must have at least one registered target in each Availability Zone that is enabled for the Gateway Load Balancer.

The target type of your target group determines how you register targets with that target group. For more information, see Target type.

Requirements

  • You cannot register instances by instance ID if they are in a VPC that is peering to the load balancer VPC (same Region or different Region). You can register these instances by IP address.

Register or deregister targets by instance ID

An instance must be in the running state when you register it.

New console

To register or deregister targets by instance ID using the new console

  1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.

  2. On the navigation pane, under LOAD BALANCING, choose Target Groups.

  3. Choose the name of the target group to open its details page.

  4. Choose the Targets tab.

  5. To register instances, choose Register targets. Select one or more instances, and then choose Include as pending below. When you are finished adding instances, choose Register pending targets.

  6. To deregister instances, select the instance and then choose Deregister.

Old console

To register or deregister targets by instance ID using the old console

  1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.

  2. In the navigation pane, under LOAD BALANCING, choose Target Groups.

  3. Select the target group.

  4. Choose Targets, Edit.

  5. (Optional) For Registered instances, select any instances to be deregistered and choose Remove.

  6. (Optional) For Instances, select any running instances to be registered and then choose Add to registered.

  7. Choose Save.

Register or deregister targets by IP address

An IP address that you register must be from one of the following CIDR blocks:

  • The subnets of the VPC for the target group

  • 10.0.0.0/8 (RFC 1918)

  • 100.64.0.0/10 (RFC 6598)

  • 172.16.0.0/12 (RFC 1918)

  • 192.168.0.0/16 (RFC 1918)

New console

To register or deregister targets by IP address using the new console

  1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.

  2. On the navigation pane, under LOAD BALANCING, choose Target Groups.

  3. Chose the name of the target group to open its details page.

  4. Choose the Targets tab.

  5. To register IP addresses, choose Register targets. For each IP address, select the network, Availability Zone, IP address, and port, and then choose Include as pending below. When you are finished specifying addresses, choose Register pending targets.

  6. To deregister IP addresses, select the IP addresses and then choose Deregister. If you have many registered IP addresses, you might find it helpful to add a filter or change the sort order.

Old console

To register or deregister targets by IP address using the old console

  1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.

  2. In the navigation pane, under LOAD BALANCING, choose Target Groups.

  3. Select the target group and choose Targets, Edit.

  4. To register IP addresses, choose the Register targets icon (the plus sign) in the menu bar. For each IP address, specify the network, Availability Zone, IP address, and port, and then choose Add to list. When you are finished specifying addresses, choose Register.

  5. To deregister IP addresses, choose the Deregister targets icon (the minus sign) in the menu bar. If you have many registered IP addresses, you might find it helpful to add a filter or change the sort order. Select the IP addresses and choose Deregister.

  6. To leave this screen, choose the Back to target group icon (the back button) in the menu bar.

Register or deregister targets using the AWS CLI

Use the register-targets command to add targets and the deregister-targets command to remove targets.