How-to guides

• 1: Launch Configuration
• 2: Managing Policies
• 3: Managing Schedules
• 4: Managing Notifications

1 - Launch Configuration

To create an Auto-Scaling Group, you need to create a Launch Configuration in advance.

Creating a Launch Configuration

You can create a Launch Configuration service on the Samsung Cloud Platform Console and use it.

To create a Launch Configuration, follow these steps:

1. Click All Services > Compute > Virtual Server menu. It moves to the Service Home page of Virtual Server.

2. Click the Launch Configuration menu. It moves to the Launch Configuration list page.

3. Click the Create Launch Configuration button on the Launch Configuration list page. It moves to the Create Launch Configuration page.

4. Select the required information in the Image and Version Selection section of the Create Launch Configuration page and click the Next button.

   Note

   The images that can be selected in the Launch Configuration are as follows: Virtual Server OS Image Provided Version.

5. Enter the required information in the Service Information Input section of the Create Launch Configuration page.

   Category	Required	Description
   Launch Configuration Name	Required	The name of the Launch Configuration A name to distinguish the Launch Configuration
   Service Type > Server Type	Required	The server type of the Launch Configuration Standard: Standard specifications commonly used High Capacity: Server specifications with higher capacity than Standard Refer to Virtual Server Server Type for the available server types
   Block Storage	Required	Block Storage settings according to the purpose of the Launch Configuration Basic OS: The area where the OS is installed and used The capacity is entered in Units, and the minimum capacity varies depending on the OS image type Alma Linux: Enter a value between 2 and 1,536 Oracle Linux: Enter a value between 5 and 1,536 RHEL: Enter a value between 2 and 1,536 Rocky Linux: Enter a value between 2 and 1,536 Ubuntu: Enter a value between 1 and 1,536 Windows: Enter a value between 4 and 1,536 SSD: High-performance general volume HDD: General volume SSD/HDD_KMS: Additional encrypted volume using Samsung Cloud Platform KMS (Key Management System) encryption key Encryption can only be applied when created, and cannot be changed after creation Using the SSD_KMS disk type may cause performance degradation Add: Additional user space outside the OS area Select Use and enter the storage type and capacity Click the + button to add storage, and click the x button to delete (up to 25 can be added) Capacity is entered in Units, and enter a value between 1 and 1,536 1 Unit is 8GB, so 8 to 12,288GB is created SSD: High-performance general volume HDD: General volume SSD/HDD_KMS: Additional encrypted volume using Samsung Cloud Platform KMS (Key Management System) encryption key Encryption can only be applied when created, and cannot be changed after creation Using the SSD_KMS disk type may cause performance degradation SSD_MultiAttach: Volume that can be connected to two or more servers For more information on Block Storage types, refer to Creating Block Storage
   Keypair	Required	Select the authentication method for the Launch Configuration Server authentication information to access the server created by creating an Auto-Scaling Group with the Launch Configuration Create New: Create a new Keypair if needed Refer to Creating a Keypair for how to create a new Keypair Default access account list by OS Alma Linux: almalinux RHEL: cloud-user Rocky Linux: rocky Ubuntu: ubuntu Windows: sysadmin

   Table. Launch Configuration Service Information Input Items

6. Enter the information in the Additional Information Input section of the Create Launch Configuration page and click the Next button.

   Category	Required	Description
   Init Script	Optional	Script that runs when the server starts using the Launch Configuration Enter within 45,000 bytes The Init Script must be a batch script for Windows or a shell script or cloud-init for Linux, depending on the selected image.
   Tag	Optional	Add a tag Up to 50 tags can be added per resource Click the Add Tag button, enter the Key and Value, or select them

   Table. Launch Configuration Additional Information Input Items

7. Check the input information and estimated cost on the Create Information Confirmation page, and click the Complete button.

   • After creation is complete, check the created Launch Configuration on the Launch Configuration list page.

Checking Launch Configuration Details

The Launch Configuration service allows you to check the overall resource list and detailed information, and modify it. The Launch Configuration details page consists of Details, Tags, and Work History tabs.

To check the Launch Configuration details, follow these steps:

1. Click All Services > Compute > Virtual Server menu. It moves to the Service Home page of Virtual Server.
2. Click the Launch Configuration menu. It moves to the Launch Configuration list page.
3. Click the resource to check the details on the Launch Configuration list page. It moves to the Launch Configuration details page.
   • The top of the Launch Configuration details page displays status information and additional feature information, and consists of Details, Tags, and Work History tabs.

Details

You can check and modify the detailed information of the selected resource on the Launch Configuration list page.

Tags

You can check the tag information of the selected resource on the Launch Configuration list page, and add, change, or delete it.

Work History

You can check the work history of the selected resource on the Launch Configuration list page.

Deleting a Launch Configuration

You can reduce operating costs by deleting unused Launch Configurations. However, deleting a Launch Configuration may immediately stop the operating service, so you should consider the impact of stopping the service before proceeding with the deletion.

To delete a Launch Configuration, follow these steps:

1. Click All Services > Compute > Virtual Server menu. It moves to the Service Home page of Virtual Server.
2. Click the Launch Configuration menu. It moves to the Launch Configuration list page.
3. Click the resource to delete on the Launch Configuration list page. It moves to the Launch Configuration details page.
4. Click the Delete Launch Configuration button.
5. After deletion is complete, check that the resource has been deleted on the Launch Configuration list page.

2 - Managing Policies

The number of servers in an Auto-Scaling Group can be dynamically adjusted based on monitoring metrics. When the set threshold is exceeded based on the monitoring metrics, the number of servers is adjusted. At this time, you can choose one of three ways to adjust the number of servers: increase or decrease the number of servers by a specified number, increase or decrease the number of servers by a specified ratio, or fix the number of servers to a specified value. When a server is started or terminated due to a policy, the monitoring metric, such as CPU usage, may temporarily exceed the threshold set in the policy. However, since this is a temporary moment, a cooldown time is set so that it is not judged as an abnormal situation. You can add and manage policies for an Auto-Scaling Group created in the Samsung Cloud Platform Console.

Adding a Policy

You can add a policy to an Auto-Scaling Group. To add a policy to an Auto-Scaling Group, follow these steps:

1. All Services > Compute > Virtual Server menu, click. Move to the Service Home page of Virtual Server.

2. Click the Auto-Scaling Group menu. Move to the Auto-Scaling Group List page.

3. On the Auto-Scaling Group List page, click the resource to view detailed information. Move to the Auto-Scaling Group Details page.

4. Click the Policy Tab. Move to the Policy Tab page.

5. Click the Add Policy button. The Add Policy popup window opens.

   Classification	Required	Detailed Description
   Classification	Required	Policy classification Scale In: Server reduction Scale Out: Server increase
   Policy Name	Required	Policy name for distinction
   Execution Condition	Required	Condition for executing the policy Statistic: Method of calculating the metric type Average: Average of servers in the Auto-Scaling Group Min: Minimum value among servers in the Auto-Scaling Group Max: Maximum value among servers in the Auto-Scaling Group Metric Type: CPU Usage, Memory Usage, Network In(bytes), Network Out(bytes), Network In(Packets), Network Out(Packets) Note: Memory usage policy is not available for Windows servers Operator: >= > <= < Threshold: Threshold for the metric type Period: Continuous time to trigger the execution condition (N minutes)
   Execution Unit	Required	Method of executing the policy Policy Type: Select the type of policy to execute. Increase or decrease the number of servers by a specified number: Increase or decrease the target value Increase or decrease the number of servers by a specified ratio: Increase or decrease the target value ratio Fix the number of servers to a specified value: Fix the target value Target Value: Number or ratio to execute the selected Policy Type
   Cooldown	Required	Time to wait (in seconds) when a server is started or terminated due to a policy Default value is 300 seconds, and it can be set between 60 seconds and 3,600 seconds.

   Table. Add Policy Popup Items
   Note

   Policy > Cooldown Setting

   • When a server is started or terminated due to a policy, wait for the cooldown time set. The monitoring metric, such as CPU usage, may temporarily exceed the threshold set in the policy. However, since this is a temporary moment and not a condition for adjusting the number of servers, the cooldown time is set to wait.
   Guide

   Policy execution operates within the set minimum and maximum number of servers.

   • Even if the number of servers is increased or decreased, or fixed, beyond the minimum and maximum number of servers, it operates within the set minimum and maximum number of servers.
   • Example: If the minimum number of servers is 3, even if the number of servers is fixed to 1, the number of servers will not decrease to 1, but will be maintained at the minimum number of servers, which is 3.

6. In the Add Policy popup window, enter the required values and click the Confirm button. The added policy can be checked in the Policy List.

Policy Creation Example

The following is an explanation of the policy example. Refer to it when creating a policy.

Modifying a Policy

You can modify a policy of an Auto-Scaling Group. To modify a policy of an Auto-Scaling Group, follow these steps:

1. All Services > Compute > Virtual Server menu, click. Move to the Service Home page of Virtual Server.

2. Auto-Scaling Group menu should be clicked. It moves to the Auto-Scaling Group list page.

3. In the Auto-Scaling Group list page, click on the resource to check the detailed information. It moves to the Auto-Scaling Group details page.

4. Click on the Policy tab. It moves to the Policy tab page.

5. Click on the More > Edit button of the policy to be modified. The Policy modification popup opens.

   Classification	Required	Detailed Description
   Classification	Required	Policy classification Scale In: Server count return Scale Out: Server count increase
   Policy Name	Required	Policy name for distinction
   Execution Condition	Required	Condition for executing the policy Statistic: Method of calculating Metric Type Average: Average of servers in Auto-Scaling Group Min: Minimum value among servers in Auto-Scaling Group Max: Maximum value among servers in Auto-Scaling Group Metric Type: CPU Usage, Memory Usage, Network In(bytes), Network Out(bytes), Network In(Packets), Network Out(Packets) Note: Memory usage policy cannot be set for Windows servers Operator: >= > <= < Threshold: Threshold corresponding to Metric Type Period: Continuous time (N minutes) to trigger the execution condition
   Execution Unit	Required	Method of executing the policy Policy Type: Select the type of policy to be executed. Increase or decrease the server count by a specified number: Increase or decrease the server count by the target value Increase or decrease the server count by a specified ratio: Increase or decrease the server count by the target value ratio Fix the server count to the input value: Fix the server count to the target value Target Value: The number or ratio of the selected Policy Type to be executed
   Cooldown	Required	Waiting time (in seconds) when a server is started or terminated due to a policy Default value is 300 seconds, and it can be set from 1 second to a maximum of 3,600 seconds

   Table. Policy modification popup items

6. Click the Confirm button after entering the required values in the Policy modification popup window.

Policy Addition and Modification Restrictions

There are restrictions when adding or modifying policies, depending on the policy classification, execution condition, and execution condition range. Refer to the examples of restrictions below and add or modify policies accordingly.

Example 1 - Check for duplicate registration of policy classification and execution condition

Duplicate registration is not allowed when the policy classification (Scale Out or Scale In) and execution condition (Metric type) are the same.

If a policy is already registered as shown above, it is not possible to add or modify a policy with the same classification (Scale Out) and execution condition (Metric type = CPU Usage).

Example 2 - Check the execution condition range for the same execution condition (Metric type) and execution condition (Statistic)

When the policy distinction (Scale Out or Scale In) is different, the execution condition range (Comparison operator + Threshold) cannot be duplicated for the same execution condition (Metric type) and execution condition (Statistic).

In the case where a policy is registered as above, it is not possible to add a policy or modify it as follows: If the CPU Usage is 60% or higher on average, since the Scale Out policy is already registered, it is not possible to register a Scale In policy for CPU Usage average of 60% or lower, as the 60% case would be a duplicate of the same execution condition.

If a policy is already registered as shown above, it is not possible to add or modify a policy with the same execution condition (Metric type = CPU Usage) and execution condition (Statistic = Average), and an execution condition range that overlaps with the existing policy.

Example 3 - Check the execution condition range for the same execution condition (Metric type) and execution condition (Statistic)

When the policy distinction (Scale Out or Scale In) is different, the execution condition range (Comparison operator + Threshold) cannot be duplicated for the same execution condition (Metric type) and execution condition (Statistic).

In the case where a policy is registered as above, it is not possible to add or modify a policy as follows: Since the Scale In policy is already registered when the CPU usage is 10% or less on average, it is not possible to register a Scale Out policy when the CPU usage is less than 60%, less than or equal to 60%, greater than 10%, or greater than 9%.

Example 4 - Registration is possible when the execution condition range does not overlap

When the policy distinction (Scale Out or Scale In) is different, it is possible to register even if the execution condition (Statistic) is different or the execution condition range (Comparison operator + Threshold) does not overlap for the same execution condition (Metric type).

In the case where a policy is registered as above, it is possible to add or modify a policy as follows. If the execution condition range does not overlap or the execution condition (Statistic) is different, registration is possible.

Deleting a Policy

It is possible to delete a policy from an Auto-Scaling Group. To delete a policy, follow the procedure below.

1. All Services > Compute > Virtual Server menu, click. Move to the Service Home page of Virtual Server.
2. Auto-Scaling Group menu, click. Move to the Auto-Scaling Group List page.
3. On the Auto-Scaling Group List page, click the resource to check the detailed information. Move to the Auto-Scaling Group Details page.
4. Click the Policy Tab. Move to the Policy Tab page.
5. Select the policy to delete and click the Delete button. The Policy Delete Confirmation popup window opens.
6. Confirm the Policy Delete Confirmation popup window and click the Confirm button.

3 - Managing Schedules

You can schedule daily, weekly, monthly, or one-time, and set the desired number of servers at a fixed time. This is useful when it is possible to predict when to reduce or increase the number of servers.

Add schedule

You can add a schedule to the Auto-Scaling Group. To add a schedule to the Auto-Scaling Group, follow these steps.

1. Click All Services > Compute > Virtual Server menu. It moves to the Service Home page of Virtual Server.
2. Auto-Scaling Group menu is clicked. It moves to the Auto-Scaling Group list page.
3. Auto-Scaling Group list page, click the resource to check the detailed information. It moves to the Auto-Scaling Group details page.
4. Click the Schedule Tab. It moves to the Schedule Tab page.
5. Click the Add Schedule button. The Add Schedule popup window opens.

   Classification	Required	Detailed Description
   Schedule Name	Required	Schedule-specific distinguishing name
   Server count selection	Required	When performing a schedule, select the number of servers to adjust Min: The minimum number of servers that the Auto-Scailg Group will maintain Desired: The target number of servers within the Auto-Scailg Group Max: The maximum number of servers that the Auto-Scailg Group can maintain
   Enter the number of servers	Required	Enter the value of the selected server number Min value: Please enter a value between 0 and 50. (Min≤Desired≤Max) Desired value: Please enter a value between 0 and 50. (Min≤Desired≤Max) Max value: Please enter a value between 0 and 50. (Min≤Desired≤Max)
   Period	Required	Schedule execution period Daily: You can set the start date and end date, and permanent settings for daily schedule execution. You can also set time and time zone Weekly: You can set start date and end date, permanent settings, and time and time zone settings. You can also select the day of the week for weekly schedule execution Monthly: You can set start date and end date, permanent settings, and time and time zone settings. You can also enter the date for monthly schedule execution Once: You can set time and time zone settings. You can also set the date for one-time schedule execution
   Start Date	Select	Set schedule start date Cannot be set to a date prior to the current date. The default is the current date.
   End Date	Select	Set schedule end date Cannot be set to a date prior to the current date. The default is the current date + 7.
   Permanent	Select	If permanent is set, the schedule end date is set to 9999-12-31
   Time	Required	Schedule execution time setting Can be set in 30-minute units. Time faster than the current date and time cannot be set
   Time Zone	Required	Time zone corresponding to the schedule execution time (e.g., Asia/Seoul (GMT +09:00))
   Day of the week	Required	If you select cycle as every week, select the day of the week to perform the schedule
   Date	Essential	Cycle is selected as every month, enter the Date to perform the schedule Please enter one or more between -31 and 31, excluding 0. (Example: 3,4,5) Cycle is selected as once, set the Date to perform the schedule It cannot be set before the current date. The default value is the current date.

   Table. Schedule Add Popup Item
6. In the Add Schedule popup window, enter the required values and click the OK button.
7. Check the message in the Add Schedule Confirmation popup window, then click the Confirm button.

Modify Schedule

You can modify the schedule of the Auto-Scaling Group. To modify the schedule of the Auto-Scaling Group, follow these steps.

1. Click All services > Compute > Virtual Server menu. It moves to the Service Home page of Virtual Server.

2. Auto-Scaling Group menu is clicked. It moves to the Auto-Scaling Group list page.

3. Auto-Scaling Group list page, click the resource to check the detailed information. Move to the Auto-Scaling Group details page.

4. Click the Schedule Tab. It moves to the Schedule Tab page.

5. Click the More > Edit button of the schedule you want to modify. The Edit Schedule popup window will open.

   Classification	Required	Detailed Description
   Schedule Name	Required	Schedule name to distinguish by schedule
   Number of servers to select	Required	When performing a schedule, select the number of servers to adjust Min: The minimum number of servers that the Auto-Scailg Group will maintain Desired: The target number of servers within the Auto-Scailg Group Max: The maximum number of servers that the Auto-Scailg Group can maintain
   Enter the number of servers	Required	Enter the value of the selected server number Min value: Please enter a value between 0 and 50. (Min≤Desired≤Max) Desired value: Please enter a value between 0 and 50. (Min≤Desired≤Max) Max value: Please enter a value between 0 and 50. (Min≤Desired≤Max)
   Period	Required	Schedule execution period Daily: You can set the start date and end date, and permanent settings for daily schedule execution. You can also set time and time zone Weekly: You can set start date and end date, permanent settings, and time and time zone. You can also select the day of the week for weekly schedule execution Monthly: You can set start date and end date, permanent settings, and time and time zone. You can also enter the date for monthly schedule execution Once: You can set time and time zone. You can also set the date for one-time schedule execution
   Start Date	Select	Set schedule start date Cannot be set to a date prior to the current date. The default is the current date.
   End Date	Select	Set schedule end date Cannot be set to a date prior to the current date. The default is the current date + 7.
   Permanent	Select	If permanent is set, the schedule end date is set to 9999-12-31
   Time	Required	Schedule execution time setting Can be set in 30-minute units. Time faster than the current date and time cannot be set
   Time Zone	Required	Time zone corresponding to the schedule execution time (e.g. Asia/Seoul (GMT +09:00))
   Day	Required	If you select Weekly as the Cycle, select the day of the week to perform the schedule
   Date	Essential	Cycle를 Every Month selected, enter the Date to perform the schedule Please enter one or more from -31 to 31 excluding 0. (Example: 3,4,5) Cycle를 Once selected, set the Date to perform the schedule Cannot be set before the current date. The default value is the current date.

   Fig. Schedule modification popup item

6. In the Modify Schedule popup window, enter the required values and click the Confirm button.

7. Schedule Modification Confirmation Check the message in the popup window and click the Confirm button.

Delete Schedule

You can delete the schedule of the Auto-Scaling Group. To delete the schedule of the Auto-Scaling Group, follow the next procedure.

1. Click All Services > Compute > Virtual Server menu. It moves to the Service Home page of Virtual Server.
2. Auto-Scaling Group menu is clicked. It moves to the Auto-Scaling Group list page.
3. Auto-Scaling Group list page, click the resource to check the detailed information. Move to the Auto-Scaling Group details page.
4. Click the Schedule Tab. It moves to the Schedule Tab page.
5. Select the schedule to be deleted and click the Delete button. The Schedule Deletion Confirmation popup window will open.
6. Schedule deletion confirmation popup window, confirm and click the Confirm button.

4 - Managing Notifications

You can specify the notification recipient to send a notification message via E-mail or SMS for a specific situation.

Add Alert

You can add notifications to the Auto-Scaling Group. To add notifications to the Auto-Scaling Group, follow these steps.

1. All services > Compute > Virtual Server menu, click. It moves to the Service Home page of Virtual Server.
2. Auto-Scaling Group menu is clicked. It moves to the Auto-Scaling Group list page.
3. Click the resource to add notification information on the Auto-Scaling Group list page. It moves to the Auto-Scaling Group details page.
4. Notification Tab을 클릭하세요. Notification Tab 페이지로 이동합니다.
5. Click the Add Notification button. The Add Notification popup window opens.
6. In the Add Notification popup window, enter the required values and click the Confirm button.

   Division	Detailed Description
   Notification Point	Notification point when Auto-Scaling Group alert occurs Server creation, Server termination, Server creation failure, Server termination failure, When policy execution conditions are met Multiple selections are possible
   Notification Recipient	User to receive notification when notification occurs Add Notification Recipient button to select user Only Samsung Cloud Platform users can be selected as recipients

   Table. Notification Items

7. Check the message in the Add Alert Confirmation popup window, then click the Confirm button.

Modify Alert

You can modify the notification information of the Auto-Scaling Group. To modify the notification information of the Auto-Scaling Group, follow the procedure below.

1. Click All Services > Compute > Virtual Server menu. It moves to the Service Home page of Virtual Server.
2. Auto-Scaling Group menu will be clicked. It moves to the Auto-Scaling Group list page.
3. Click the resource to modify the notification information on the Auto-Scaling Group list page. It moves to the Auto-Scaling Group details page.
4. Click the Notification Tab. It moves to the Notification Tab page.
5. Click the More > Edit button for the notification information you want to modify in the notification list. The Edit Notification popup window opens.
6. Modify Notification In the notification modification popup window, modify the notification information and click the Confirm button.

   Classification	Detailed Description
   Notification Point	Notification point when Auto-Scaling Group alert occurs Server creation, Server termination, Server creation failure, Server termination failure, When policy execution conditions are met Multiple selections are possible

   Table. Notification Modification Items
7. Check the message in the Notification Modification Confirmation popup window, then click the Confirm button.

Delete Notification

You can delete the notification of Auto-Scaling Group. To delete the notification of Auto-Scaling Group, follow the procedure below.

1. 모든 서비스 > Compute > Virtual Server menu should be clicked. It moves to the Service Home page of Virtual Server.
2. Auto-Scaling Group menu is clicked. It moves to the Auto-Scaling Group list page.
3. Auto-Scaling Group list page, click the resource to modify the notification information. Move to the Auto-Scaling Group details page.
4. Click the Notification Tab. It moves to the Notification Tab page.
5. Select the notification to be deleted from the notification list, then click the Delete button. The Delete Notification Confirmation popup window will open.
6. Notification deletion confirmation popup window, confirm and click the Confirm button.