You can configure VM Auto Scaling via DCD. This feature combines granular configurable options wherein you can create a group and define when the feature must scale in or scale out based on demand. You must also specify the minimum (for scale out) and the maximum (for scale in) number of replicas a group can contain for the replicas to stay within the given threshold.

Configure replicas after configuring thresholds and policies, where you define the settings, network, and storage volumes for the replicas created by the feature. After you define the network, you may add an Application Load Balancer (ALB) to the group.

After successfully creating a group, you can modify its details, delete it, and view its associated servers and list of jobs.

Quick Links

The following links redirect you to the relevant pages.

In the Replica Configuration tab, you can configure the size, networks, and storage volumes for the VM instances that VM Auto Scaling creates. You may also use the CloudInit mechanism to configure VM instances.

You can configure the following on the Replica Configuration tab:

• Configure settings, network or volumes

• Associate an Application Load Balancer (ALB)

Configure VM Replicas

To configure VM replica settings, follow these steps:

1. Go to the Replica Configuration tab in the Create VM Auto Scaling Group window and configure the Settings, Network, and Volumes tabs.

1. Click Create to configure your VM Auto Scaling Group.

Associate an Application Load Balancer (ALB)

An Application Load Balancer (ALB) from the VDC can be associated with the replica configuration. As a result, a replica can be linked to multiple target groups if a target group contains several NICs. This way an ALB ensures that the load is equally distributed among the replicas.

When you associate an ALB with a replica configuration, the ALB can use all of the VM replicas created by the VM Auto Scaling feature, which means your application can scale and receive requests from different queries based on the configured ALB.

To associate an ALB with a replica configuration, go to the Replica Configuration tab in the Create VM Auto Scaling Group window and specify the following:

1. Target Group: Select a value from the drop-down list. You can also click Create new Target Group from the drop-down list to instantly create a new target group. When you specify a target group, the scaling process associates replicas with the target groups. The ALB checks these target groups to verify the available IP addresses to process requests.

1. Port: Select a value from the drop-down list to decide the port on which the queries must be redirected. It is recommended to set the port to TCP port 80. This port is used by the ALB to distribute traffic to individual replicas.

2. Weight: The traffic is distributed proportionally to the target weight, which is the ratio of the total weight of all targets. A target with a higher weight receives a larger share of traffic. The valid range is from 1 to 256. We recommend using values in the middle range to leave room for later adjustments.

Introduction

IONOS VM Auto Scaling is a cloud computing feature that modifies the number of instances in your automatically based on changes in demand (or the load on your VM).

VM Auto Scaling automatically adds new VM instances when the load increases and reduces the number of instances when the load decreases. This automatic behavior constantly monitors the load and regularly scales the number of VM instances based on the policy threshold. The functionality ensures that the number of replicas in the group remains within the defined limitations.

To configure the feature, create a VM Auto Scaling Group with the following settings:

• A group-wide scaling policy based on metrics.

• Server replica configuration to automatically add or remove VMs based on demand.

VM Auto Scaling generates or deletes replicas based on the scaling policy, as needed by your application. The metric-based scaling policy tracks the CPU usage or the incoming and outgoing network packets, based on the configuration. When the existing VM instances hit the given threshold, it automatically initiates scaling, either scale in or scale out. Scaling in and scaling out is also called horizontal scaling because it adds additional VMs of the same size but does not increase the size of individual VMs by adding new cores or storage.

Additionally, you can replicate the configuration, such as the CPU architecture, number of cores, network, and group volumes.

VM Auto Scaling interfaces with other IONOS Cloud services, such as the , to maximize resource utilization, improve application scalability, and high-availability of multiple application servers due to server redundancy. You can specify how VM Auto Scaling replicas should be included in the ALB. When enabled, your application automatically scales based on requests from various sources. For example, if you pair VM Auto Scaling with an ALB and your application includes a web service, VM Auto Scaling ensures that your application has enough VM instances to process all requests.

VM Auto Scaling is cost-efficient and improves resource utilization. You pay only for the resources needed to run your application without any additional costs.

You can access and configure VM Auto Scaling via the , Cloud API, and the SDK. To start using VM Auto Scaling, see .

Product Overview

Get an overview of VM Auto Scaling.

API Reference

Get started with VM Auto Scaling via the API.

How-To's

Get started with VM Auto Scaling via the DCD.

Frequently Asked Questions (FAQs)

After successfully configuring your VM Auto Scaling Groups, you can modify scaling thresholds and scaling policies, update replica configuration or associate an ALB via the VM Auto Scaling Manager.

To modify the values, follow these steps:

1. Log in to DCD with your username and password.

2. Go to Menu > Management > VM Auto Scaling.

3. Click on the respective group to modify its values.

4. You can modify the following:

• click to update the name of the group, modify scaling thresholds and policies.

• click to update storage settings, NICs and associated ALBs, or storage volumes.

• click to view the servers that are associated with the group.

• click to view the list of tasks.

1. Click Save to save the changes.

The VM Auto Scaling Manager displays the list of all servers associated with the selected VM Auto Scaling Group. Each server is given a unique identification string as its name automatically.

To view the associated servers, follow these steps:

1. Log in to DCD with your username and password.

2. Go to Menu > Management > VM Auto Scaling.

3. Click Servers to view one of these:

   • click Console to open the remote console to access your VM.

   • clicking Focus Server opens the VDC and preselects the server automatically.

What is VM Auto Scaling?

VM Auto Scaling is a managed service designed to launch or terminate VM instances horizontally to ensure you have the appropriate number of instances available to handle the load on your application.

What are the benefits of VM Auto Scaling?

You can optimize cost by reducing the number of VMs needed to run in parallel while ensuring your setup does not run into resource limitations.

Why did my setup scale up or scale down?

One of your scaling policies was met. For example, when CPU utilization exceeds the defined threshold, you may check the Auto Scaling logs to see why a scaling action was triggered.

What is a VM Auto Scaling Group?

It is a defined group of VMs created from the same image template by the VM Auto Scaling feature.

What happens to my VM instances if I delete my VM Auto Scaling Group?

When you delete the VM instances, all the underlying VMs will be deleted.

How do I know when VM Auto Scaling adds or deletes VM instances?

The tab contains information about the scaling operations that the feature initiates. You can view a list of actions triggered by the feature, its status, and when the process started.

How do I propagate changes to existing VMs in my VM Auto Scaling Group?

If not explicitly configured differently, VM Auto Scaling deletes the oldest VM in your Auto Scaling group first when a scale in action is triggered. Thus changes will be propagated naturally through your group of VMs.

When your VM Auto Scaling Group qualifies for a scale in action according to the metrics you set, the oldest running VM in your group will be stopped. You repeat this process until all VMs are updated.

What are the different ways to scale IONOS resources?

Currently, VM Auto Scaling only supports horizontal scaling. This means that the feature creates more VMs to support your workload based on the replica configuration of the appropriate group.

What happens to the volumes after the scale in process?

You can choose if the volumes must be retained when a VM is scaled in. Remember that choosing to retain the volumes during scale in process accumulates data over time.

How can I get the most use out of VM Auto Scaling?

You can combine VM Auto Scaling with an ALB to spread the load evenly across your VMs. You may also use CloudInit to configure your VMs during bootup based on the workload.

Can I connect replicas on two different subnets?

A Cross Connect is a feasible alternative to connect replicas on two different subnets. Hence, groups with replicas connected to these subnets will be connected via Cross Connect. Moreover, ensure that you make the necessary configurations as you would for VMs to communicate with one another. The approach is similar to physically connecting two subnets using a network cable.

Do the replicas created as a part of VM Auto Scaling work with other IONOS services?

Yes, the replicas (or VM instances) created as part of the scaling process function in the same way as the IONOS Cloud VMs configured in the VDC. For example, you can configure it with an ALB, Network Load Balancer, NAT Gateway, Managed Kubernetes clusters, and MongoDB clusters.

Deletion of a VM Auto Scaling Group results in the deletion of all the VMs associated with the respective group.

To delete a group, follow these steps:

1. Log in to DCD with your username and password.

2. Go to Menu > Management > VM Auto Scaling.

3. Click Delete to delete the selected group.

4. Select the checkbox to confirm deletion.

5. Enter your Password to proceed with the deletion process.

6. Select the Skip password verification for the next 60 minutes checkbox if you want to avoid specifiying your password for any operation during the next 60 minutes.

7. Click OK.

VM Auto Scaling Groups are a collection of virtual servers that automatically scale the number of VM replicas based on the metrics.

Follow these steps to configure a VM Auto Scaling , and define thresholds and scaling policies:

1. Log in to DCD with your username and password.

2. Go to Menu > Management > VM Auto Scaling.

3. Click Create to create a group and define replicas. The Create VM Auto Scaling Group window displays the Configuration and the Replica Configuration tabs.

4. Define the following in the Configuration tab:

• Create a VM Auto Scaling Group

• Define Scaling Thresholds

• Define Scaling In Policies

• Define Scaling Out Policies

5. Configure replicas. For more information, see Configure replicas.

6. Click Create to save the configuration.

Create a VM Auto Scaling Group

You can specify a name for your VM Auto Scaling Group and the minimum number and the maximum number of VM instances it can contain during scaling. The minimum number ensures that you never run out of VM instances and the group always has at least one VM instance. The feature cannot provide more than the maximum number of VM instances during a scale out operation.

To create a VM Auto Scaling Group, go to the Configuration tab in the Create VM Auto Scaling Group window and specify the following:

1. Name: Enter a name for the VM Auto Scaling Group.

2. Data Center: Select a data center from the drop-down list. You can either select an existing Virtual Data Center (VDC) or create a new one if required. The application lists all the VDCs in your DCD. The group is valid only within the selected VDC to which it belongs.

3. Minimum Count: Enter the minimum number of VMs the group must scale to. The minimum replica count is one. VM Auto Scaling uses this as a reference value to stop deleting VM instances for a group. This is necessary to ensure that scaling does not reduce the VM instances beyond the specified count.

4. Maximum Count: Enter the maximum number of VMs the group must scale to. VM Auto Scaling uses this as a reference value to stop adding new VM instances for a group. This is necessary to ensure that scaling does not increase beyond the specified count. To improve the efficiency of the VM Auto Scaling service, we recommend limiting the maximum number of VMs in an Auto Scaling Group to 100 or less.

Define Scaling Thresholds

A Policy defines the rules to trigger VM Auto Scaling to analyze the resource utilization rate at regular intervals. You can only define one metric policy per group that triggers the scaling process.

To define policies, go to the Configuration tab in the Create VM Auto Scaling Group window and specify the following:

1. Metric: Select a metric from the drop-down list whose performance must be monitored. The pre-defined values are based on the CPU utilization average or network bytes for incoming and outgoing bytes or packets.

2. Scale In Threshold: Enter a value to specify when VM Auto Scaling must trigger the scale in operation. The value specified here indicates the percentage of the CPU utilization rate or the network packets or network bytes, based on which the scale in action is triggered for the metric. For example, if you specify the CPU utilization rate as 30, VM Auto Scaling automatically begins scaling inwards and deletes the additional VM instances when the CPU utilization rate is 30%.

3. Scale Out Threshold: Enter a value to specify when VM Auto Scaling must trigger the scale out operation. The value specified here indicates the percentage of the CPU utilization rate or the network packets or bytes based on which the scale-out action is triggered for the metric. For example, if you specify the value as 70, the application automatically begins scaling outwards and adds additional VM instances when the CPU utilization rate reaches 70%.

1. Range: Enter a time range in hours, minutes, or seconds. Example: 1h, 3m, 120s. It is the period during which VM Auto Scaling measures the percentage of chosen metric utilization at regular intervals and automatically scales in or scales out based on the demand. If specifying in seconds, ensure that the value is not less than 120 seconds.

2. Unit: Select a unit from the drop-down list. You can specify whether the scaling process should be initiated every hour, minute, or second for other predefined metrics. This is automatically set to Total for an instance CPU utilization average metric.

Define Scaling In Policies

Scale in defines the action triggered during a scale in operation. Based on the values defined, the feature automatically deletes the specified number of VM instances after the cooldown period.

To define scale in policies, go to the Configuration tab in the Create VM Auto Scaling Group window and specify the following:

1. Amount Type: Select a value from the drop-down list to define the number of replicas that must be deleted. You can choose either Percentage or Absolute.

2. Amount: Enter the number of VM instances to be deleted during a scale in operation. The minimum value is one. Scale in jobs with a large number of VMs may encounter performance issues. Hence, we recommend limiting the deletion of VMs to at most five, regardless of whether the Amount Type is absolute or percentage.

3. Cooldown Period: Enter the cooldown period to indicate the interval between each auto scaling action in the group. The cooldown period can be measured in minutes, seconds, or hours. For example, when the value is set to 5m, the scale in action is activated every 5 minutes. VM Auto Scaling automatically deletes the given number of VM instances when the resource consumption is lower.

1. Termination Policy: Select a value from the drop-down list to choose whether the oldest or the most recent replica must be deleted first. Choosing the Oldest replica first delegates the scaling process to delete the oldest replicas. Otherwise, choose the Youngest replica first to begin scaling by deleting the most recent replica.

2. Delete attached volumes: Select a value from the drop-down list to indicate if the attached volumes must be deleted. Choose Don’t delete to retain the attached volumes; otherwise, choose Delete.

Define Scaling Out Policies

Scale out defines the action triggered during a scale out operation. The feature automatically adds the specified number of VM instances after the cooldown period based on the demand.

To define scaling out policies, go to the Configuration tab in the Create VM Auto Scaling Group window and specify the following:

1. Amount Type: Select a value from the drop-down list to define the number of replicas added when the metric utilization exceeds the specified amount. You can choose either Percentage or Absolute.

2. Amount: Enter a number to indicate the number of VM instances that must be added. The minimum value is one. Scale out jobs with a large number of VMs may encounter performance issues. Hence, we recommend limiting the addition of VMs to at most five, regardless of whether the Amount Type is absolute or percentage.

3. Cooldown Period: Enter the cooldown period to indicate the interval between each auto scaling process in the group. The cooldown period can be measured in minutes, seconds, or hours. For example, when the value is set to 5m, the scale out process is activated every 5 minutes. VM Auto Scaling automatically adds the given number of VM instances when the resource consumption is higher. The notes mentioned in scale in policies are also applicable to scale out policies.

VM Auto Scaling allows you to automatically scale the number of VM instances horizontally based on the configured policy. This functionality ensures that you have enough VM instances to handle the application loads. It improves efficiency by ensuring that adequate instances are available during peak workloads and saves money by limiting the number of instances available during low workload periods.

This section covers the components of VM Auto Scaling, its features, benefits, and limitations.

Components of VM Auto Scaling

The following components are an integral part of VM Auto Scaling:

• Auto Scaling group: A collection of VM instances that the VM Auto Scaling manages. VM Auto Scaling automatically adds or removes instances from the group based on the metrics defined for the consumption of resources in the scaling policy.

• Scaling policy: Defines how VM Auto Scaling Group scales an instance group based on various parameters such as CPU usage, incoming or outgoing requests, or load balancing utilization. Users can define custom scaling policies and set the desired scaling parameters for the instance group.

• VM replica configuration: Defines the properties of the new VM replicas created during the scaling process. The configuration includes the parameters such as CPU type, number of cores, RAM size, network, and volumes.

• VM Auto Scaling Manager: Create a VM Auto Scaling Group, define scaling policies, and replicate settings for creating VM instances.

VM Auto Scaling Features

VM Auto Scaling provides the following features:

• Automatic Scaling automatically adds or removes VM instances based on the need. It analyzes the resource consumption continuously and scales up the allotted resources when necessary to ensure that the application is always responsive and performing optimally.

• Customizable scaling policies allow users to define custom scaling policies based on various parameters, such as CPU usage or network utilization and set the desired scaling parameters for the Auto Scaling group.

• Multiple granular scaling policies allow you to specify the number of instance creations when the scaling threshold is reached. Users may choose a policy that best suits their workload requirements.

• Integration with other IONOS Cloud services, such as the ALB, enables users to optimize resource utilization and improve application scalability.

VM Auto Scaling Benefits

VM Auto Scaling provides the following benefits:

• Improved resource utilization enables you to allocate resources as needed, thus, improving resource utilization and cost efficiency.

• Improved application performance ensures the application is always responsive and performing optimally, thus providing a better user experience.

• Improved scalability allows you to scale the application easily and quickly, supporting business growth and increasing revenue.

• Reduced operational overhead automates the scaling process, reducing the operational overhead of managing and maintaining VM instances.

Limitations of VM Auto Scaling

This section lists the limitations of VM Auto Scaling:

• It is best suited for a gradual increase in demand. The feature uses cooldown timers to scale resources gradually rather than abruptly. As a result, if you anticipate a sudden rise in traffic, we recommend manually adding VMs ahead of time. For example, you could add new VMs before traffic spikes after a TV commercial.

• The capabilities are limited to your customer contract limits. For more information about the contract resource limits in DCD, see Resource Overview.

• Updating the replica configuration does not affect the existing replicas; however, the changes are only visible when you create new replicas.

• To improve the efficiency of the VM Auto Scaling service, we recommend limiting the maximum number of VMs in an Auto Scaling Group to 100 or less. Note that the minimum replica count is one.

• Scale in or scale out jobs with a large number of VMs may encounter performance issues. Hence, we recommend limiting the creation or deletion of VMs to at most five, regardless of whether the Amount Type is absolute or percentage.

The scale in and scale out operations performed by the VM Auto Scaling feature are displayed in a chronological order.

To view the list of operations and their statuses, follow these steps:

1. Log in to DCD with your username and password.

2. Go to Menu > Management > VM Auto Scaling.

3. Click on the corresponding VM Auto Scaling Group to view its status. The application displays the following information:

• The Status of a job indicates whether it is completed successfully, in progress, or failed.

• An Action indicates if the feature scaled in (deleted) or scaled out (added) VM instances.

• The Timestamp provides the date and time when the process began.