Create and manage target group

This guide explains how to create and manage a target group (Target Group) including viewing the list, editing settings, and configuring listener connections.

Create target group

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target group.

2. Click the [Create target group] button at the top right.

3. On the Step 1: Configure target group screen, enter settings and click [Next].

   

   Section	Field	Description
   Load balancer	Availability zone	Select an availability zone from the project
   	Load balancer	Lists all load balancers in the selected zone
   	Listener	Lists all listeners for the selected load balancer and provides 'Do not select listener' option
   Basic info	Target group name	Enter a name for the target group
   	Protocol	Selectable protocols depending on the listener protocol: - HTTP listener: HTTP, PROXY - HTTPS listener: HTTP
   	Algorithm	Select one of Round Robin, Least Connections, Source IP: - Round Robin: Distributes traffic sequentially - Least Connections: Routes traffic to targets with fewer connections - Source IP: Sends traffic from the same source IP to the same target
   	Sticky session	Configurable only for specific listener-target group combinations: - HTTP x HTTP, TCP x TCP, UDP x UDP - Others: Fixed as "Disabled"
   	Sticky session type	Options depend on the listener-target group combination: - HTTP x HTTP: HTTP cookie, App cookie - TCP x TCP: Source IP - UDP x UDP: Source IP
   	Stickiness duration	Only enabled when sticky session uses HTTP or App cookie - Range: 1–604800 (default: 3600s for HTTP cookie, 360s for others)
   	Cookie name	Required for App cookie: - Custom app cookie name - Allowed characters: alphanumeric and ! # $ % ^ & _ * + ~ - - Max length: 255 characters
   Health check	Enable health check	Toggle usage
   	Type	Available types based on protocol: - HTTP group: HTTP, PING - PROXY group: PING, TCP
   	HTTP method	Only when type is HTTP - Options: CONNECT, DELETE, GET, HEAD, OPTIONS, PATCH, POST, PUT, TRACE
   	HTTP version	Only when type is HTTP - Options: 1, 1.1
   	HTTP status code	Only when type is HTTP - Supports single codes, comma-separated codes, or hyphenated ranges
   	Check path	Enter URL path format
   	Interval	1–3600 seconds (default: 30). Must be greater than timeout
   	Timeout	1–900 seconds (default: 4). Must be less than interval
   	Success threshold	1–10 times (default: 5)
   	Failure threshold	1–10 times (default: 2)

   info

   If the algorithm is Source IP, traffic is always routed to the same target from a single source IP. Sticky session settings are not needed and will be disabled. For persistent sessions, using Source IP is recommended.

4. In Step 2: Add targets, add resources in the same VPC and zone as the selected load balancer.

5. Select instances to add as targets and enter port numbers.

6. Click [Add target].

7. Modify ports to add the same target again or remove targets.

8. After adding targets, click [Next].

9. On Step 3: Review, verify the settings and click [Create].

   info

   • After creation, configure security group settings for each target. Go to Target group details > Targets and check the health check IP. Add it to the inbound rules.
   • These IPs must be open even if health checks are not used, as they serve on the service port.

Manage target group

You can view details, update settings, delete, or add new targets to existing target groups.

View target group list

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target group.

2. View the list of target groups. Use filters to search.

   Field	Description
   Name	Name and ID of the target group
   Provisioning status	Indicates if create/update/delete is in progress
   Operating status	Indicates if the target group is active
   Protocol	Protocol used for routing traffic
   Load balancer	Load balancer name and ID
   VPC	VPC name and ID
   [More options] icon	Options: rename, configure listener, algorithm, targets, traffic weight, health check, sticky session, delete

View target group details

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target group menu.

2. Select the target group you want to view in detail.

3. In the detail view, check the information in the tabs: Details, Targets, Health checks, and Properties.

   Target group details

   Section	Description
   Details	View detailed information of the target group
   Target	View the list and details of added targets
   Health checks	View health check configuration information
   Properties	View properties of the target group

Rename target group

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target group menu.

2. Click the [More options] icon of the target group you want to rename.

3. Select Rename target group.

4. In the popup, enter the new name and click [Update].

Configure listener connection

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target group menu.

2. Click the [More options] icon of the target group whose listener connection settings you want to change.

3. Select Configure listener connection.

4. In the popup, modify the listener connection settings and click [Apply].

   • To configure listener connection: Select one or more listeners to associate with the target group.
   • To remove listener connection: Select the option to disconnect from listeners.

Set algorithm

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Click the [More] icon for the target group whose connection settings you want to change.

3. From the [More] icon menu, select Set algorithm.

4. In the Set algorithm popup window, change the algorithm and click the Apply button.

Configure target

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Select the target group for which you want to modify the target settings.

3. On the detail page, click the Target tab and then click the Configure target button.

4. In the Configure target popup window, review the registered targets, add or remove targets as needed, then click the Apply button.

   • To revert changes during editing, click the Revert button at the top of the added target list.

Set traffic weight

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Select the target group for which you want to configure traffic weight.

3. On the detail page, click the Target tab and then click the Set traffic weight button.

4. In the Set traffic weight popup window, modify the weight and click the Set button.

   • Traffic weights must be integers between 0 and 256.
   • Weights are converted using the following formula:
   • Converted weight: (weight / 256) * 100 (rounded up to the first decimal place)
   • Ratio: converted weight / total sum of converted weights

   Configure traffic weight for target group

Configure health checks

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Select the target group for which you want to configure health checks.

3. On the detail page, click the Health check tab and then click the Configure health check button.

4. In the Configure health check popup window, enable or disable the health check, or change its parameters.

   Configure health checks

   Item	Description
   Target group	Name of the current target group
   Protocol	Protocol type available based on the target group - HTTP target group: HTTP, PING - HTTPS target group: HTTPS, PING - TCP target group: PING, TCP - UDP target group: TCP, HTTP - PROXY target group: PING, TCP
   Enable health check	Type: Health check type - PING: Sends a packet and verifies the response (ICMP ping) - HTTP: Sends a packet to a specified path and verifies the response - HTTPS: Verifies the response using the same method as HTTP for certificate-enabled targets - TCP: Uses TCP protocol ports to verify the target’s state
   	Interval: Frequency of health checks (in seconds) - Range: 1 to 3600 seconds
   	Timeout: Maximum time to wait for a delayed response (in seconds) - Communication is considered failed if the target does not respond within this time - Must be less than the interval - Range: 1 to 900 seconds
   	Success threshold: Number of consecutive successful health checks required to consider the target healthy
   	Failure threshold: Number of consecutive failed health checks required to consider the target unhealthy and remove it from traffic distribution

5. If the health check type is HTTP or HTTPS, you can configure additional settings.

   Item	Description
   HTTP method	Select from GET, HEAD, OPTIONS, POST, PUT, TRACE, PATCH, DELETE, CONNECT
   HTTP version	Select either 1.0 or 1.1
   HTTP status codes	Specify expected HTTP status codes to determine successful checks - Single code example: 200, 201 - Multiple codes: 201, 202, 401, 402 - Range: 200-500
   Path	URL path for health checks

6. Click the Apply button.

info

If the targets in the group use the SELinux option from the latest CentOS distribution, the PING type health check may not work, as SELinux blocks the shell_exec_t call.

Configure sticky session

Sticky session configuration is available only for certain target groups, depending on the listener and target group protocol.

Sticky session options by listener and target group protocol

Target group\Listener	HTTP	HTTPS	TCP	UDP
HTTP	HTTP cookie, App cookie	X	X	X
HTTPS	X	X	X	X
TCP	X	X	Source IP	X
UDP	X	X	X	Source IP
PROXY	X	X	X	X

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Select the target group for which you want to configure sticky sessions.

3. On the detail page, click the Properties tab, then click the Configure sticky session button.

4. In the Configure sticky session popup window, enable or disable the feature and modify settings as needed, then click the Apply button.

Delete target group

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Click the [More] icon next to the target group you want to delete.

3. From the menu, select Delete target group.

4. In the Delete target group popup window, enter the confirmation phrase and click the Delete button.

Manage target

You can view, modify, or delete targets added to a target group.

caution

Two health check IPs are generated for each subnet that contains a target. To ensure proper health checks, allow traffic from these IPs.
Refer to View health check IP and Allow health check IP communication for configuring your security group.

View health check IP

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Select the target group for which you want to view health check IPs.

3. On the detail page, click the Target tab.

4. At the top of the tab view, click Health check IP by subnet to view the list.

Allow health check IP communication

There are two methods to allow communication with health check IPs through your security group.
Choose one of the following methods depending on your preference:

Method 1: Add inbound rules to the existing security group of the target instance

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Select the target group and view the health check IPs.

3. On the detail page, click the Target tab.

4. At the top of the tab, click Health check IP by subnet and either keep the window open or copy the IP list.

5. In the Target list section, find the instance to which communication should be allowed and click its security group name.

   • If multiple security groups are attached, select any one.
   • If a matching rule already exists in any security group, communication is already permitted.

6. In the Security group detail page, go to the Inbound rules tab and click Manage inbound rules.

7. In the Manage security group rules popup, click Add at the bottom of the Inbound rules tab.

   Manage security group rules

8. Based on the Target tab details from step 5, enter the rule information and click Apply on the right.

   Inbound rule configuration

   Item	Description
   Protocol	Protocol used for communication (TCP, UDP, ICMP, ALL) depending on the health check type - PING: ICMP - HTTP, HTTPS, TCP: TCP
   Source	Health check IPs from the target details - Register both IPs per subnet
   Port	Monitoring port of the target
   Description (optional)	Description of the rule

9. Click Close at the bottom of the popup to complete rule registration.

Method 2: Create a new security group and attach it to the target instance

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Select the target group and view the health check IPs.

3. Click the Target tab.

4. At the top of the tab, click Health check IP by subnet and either keep the window open or copy the IP list.

5. Refer to Create security group to navigate to the security group creation screen.

6. In the Create security group popup, enter a name and description, and add inbound rules.

   Create security group

7. Based on step 3's Target tab details, configure all required rules.

   • You may register all health check IPs in one security group and attach it to all target instances
     or create separate security groups per subnet containing only the relevant IPs.

   Inbound rule configuration

   Item	Description
   Protocol	Protocol used for communication (TCP, UDP, ICMP, ALL) depending on the health check type - PING: ICMP - HTTP, HTTPS, TCP: TCP
   Source	Health check IPs from the target details - Register both IPs per subnet - If using one group, register all IPs
   Port	Monitoring port of the target - Can be a single port or range
   Description (optional)	Description of the rule

8. Click Create to finish creating the security group.

9. In the Security group list, click Manage linked resources for the group, and attach the target instance.

View target

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Select the target group whose targets you want to view.

3. On the detail page, click the Target tab.

4. View the list of targets in the group. Use filters as needed to refine your search.

   Item	Description
   IP	Target IP
   Port	Target port
   Instance	Name and ID of the target instance
   Subnet	Name of the subnet containing the target
   Security group	Security group attached to the target instance
   Monitoring port	Port used for health checks
   Weight ratio	Calculated weight ratio based on input weight
   Provisioning status	Status indicating whether the target is added, being modified, or being deleted
   Operational status	Indicates whether the target is available for use
   [More] icon	Options for configuring monitoring port or detaching target

Modify target

info

You cannot change the port of an existing target. To change the port, delete the target and reconfigure it via Configure target.

Set monitoring port

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Select the target group whose monitoring port you want to change.

3. On the detail page, click the Target tab.

4. Review the target list.

5. Click the [More] icon for the target you want to update.

6. Select Set monitoring port from the menu.

7. In the Set monitoring port popup, configure the following:

   • Use same port as target: Monitoring port matches traffic port
   • Use different port: Enter a different monitoring port

8. Click the Apply button.

Detach target

1. Go to the KakaoCloud Console > Beyond Networking Service > Load Balancing > Target groups menu.

2. Select the target group containing the target to detach.

3. On the detail page, click the Target tab.

4. Review the list of added targets.

5. Click the [More] icon for the target you want to detach.

6. Select Detach target from the menu.

7. In the Detach target popup window, enter the confirmation phrase and click Detach.

info

Detaching a target does not delete the associated instance. To reattach, use Configure target.