
Amazon Elastic Container Service (ECS) is a proprietary container orchestration platform that manages Docker containers using AWS-specific task definitions, services, and integrations. While ECS provides deep integration with AWS services, it creates vendor lock-in and limits portability. Kubernetes offers a standardized, cloud-agnostic approach to container orchestration with broader ecosystem support and platform independence.
This guide outlines the migration of containerized applications from AWS ECS to Vultr Kubernetes Engine (VKE). It covers the analysis of existing ECS task definitions and services, conversion to Kubernetes manifests, replication of networking and service discovery patterns, migration of secrets and configuration, and deployment strategies that minimize downtime.
Before you begin, you need to:
Before migrating, document your existing ECS configuration to understand the components that require conversion. This analysis identifies task definitions, services, load balancers, service discovery configurations, and dependencies.
List all ECS clusters in your AWS account.
The output displays cluster ARNs for all ECS clusters in your account.
List services running in your target cluster. Replace CLUSTER-NAME with your actual cluster name.
Describe each service to understand its configuration. Replace SERVICE-NAME and CLUSTER-NAME with your actual values.
This command exports the service configuration to a JSON file for reference during migration.
Extract the task definition name from the service configuration.
The output displays the task definition ARN. Note the task definition family name and revision number for the next step.
Retrieve the task definition details. Replace TASK-DEFINITION-ARN with the ARN from the previous step.
Extract key configuration details from the task definition.
The output displays container images, resource allocations, port mappings, environment variables, secrets, and volume mounts. Save this information for converting to Kubernetes manifests.
Document the service dependencies by examining the service configuration file.
The output shows load balancer attachments, service discovery registrations, and networking settings. Note these configurations for replication in Kubernetes.
ECS awsvpc mode maps each task to an ENI. Kubernetes uses a flat pod network model. If your ECS services relied on Security Groups for east-west isolation, replicate this behavior using Kubernetes NetworkPolicies.
Create a dedicated namespace for your application to isolate resources and simplify management. This provides logical separation from other applications and enables namespace-level resource quotas and access controls.
Create a namespace for your application.
Replace my-app with a descriptive name for your application environment.
Verify that the namespace is created.
Set the namespace as the default context to avoid specifying -n my-app with every command.
All subsequent kubectl commands in this guide will deploy resources to this namespace. To deploy to a different namespace, either change the context or add the -n namespace-name flag to each command.
ECS task definitions define container images, resource limits, environment variables, and volume mounts. Kubernetes Deployments serve the same purpose using a different YAML structure. Convert your task definitions to Kubernetes manifests by mapping ECS parameters to their Kubernetes equivalents.
The following table maps common ECS task definition parameters to their Kubernetes equivalents.
Create a directory for Kubernetes manifests.
Create a Deployment manifest file. Replace my-app with your application name.
Add the following Deployment configuration. Adjust values based on your ECS task definition.
Save and close the file.
Convert CPU values from ECS units to Kubernetes millicores. ECS uses 1024 units per vCPU, while Kubernetes uses 1000 millicores per CPU.
Convert memory values from MiB to Kubernetes memory format.
ECS stores secrets in AWS Secrets Manager or Systems Manager Parameter Store. Kubernetes uses native Secret and ConfigMap resources for sensitive and non-sensitive configuration data respectively.
List secrets referenced in your ECS task definition.
The output displays secret ARNs from AWS Secrets Manager or Parameter Store.
Retrieve secret values from AWS Secrets Manager. Replace SECRET-NAME with your secret identifier.
Create a Kubernetes Secret for sensitive application data.
Replace the keys and values with your actual secrets retrieved from AWS, and repeat this step for each secret you need to create.
Create a ConfigMap for non-sensitive configuration.
Add the ConfigMap configuration.
Save and close the file.
Apply the ConfigMap to your cluster.
Update the Deployment manifest to reference the Secret and ConfigMap.
Replace the env section with envFrom references to the ConfigMap and Secret.
This configuration injects all key-value pairs from the referenced ConfigMap and Secret as environment variables inside the container.
Save and close the file.
ECS uses AWS Cloud Map for service discovery, allowing services to communicate using DNS names. Kubernetes provides built-in service discovery through Service resources backed by CoreDNS, which automatically create stable DNS records and virtual IPs for accessing pods.
Create a Service manifest for internal communication.
Add the Service configuration for the ClusterIP type, which exposes the application only inside the cluster.
In this configuration:
port is the Service port. Other pods use this port when connecting to the service.targetPort is the container port exposed by the application inside each pod.selector matches pods labeled app: my-app, dynamically updating endpoints as pods scale or restart.Save and close the file.
Apply the Service manifest.
Verify that the Service is created and has assigned a cluster IP address.
The output displays the Service details, including the CLUSTER-IP, which acts as a stable virtual IP for the application.
Applications within the cluster can now access this service using the DNS name my-app.my-app.svc.cluster.local (following the pattern <service-name>.<namespace>.svc.cluster.local) or the short name my-app when accessing from within the same namespace. Kubernetes automatically maintains this DNS record as pods are created or destroyed.
ECS integrates with Application Load Balancers (ALB) and Network Load Balancers (NLB) for external traffic routing. VKE uses the Kubernetes Gateway API with Envoy Gateway for advanced traffic management, providing equivalent functionality to ALB with path-based and host-based routing, along with automated TLS certificate provisioning.
Before creating the Gateway resource for your application, install the required components by following these sections from the Gateway API with TLS Encryption guide:
Deploy the Gateway resource to provision a Vultr Load Balancer and assign a public IP address.
Create the Gateway manifest file.
Add the following configuration. Replace myapp.example.com with your actual domain name.
Save and close the file.
Apply the Gateway manifest.
Retrieve the Gateway external IP address.
The output displays the Gateway status and assigned IP address. Note this IP address for DNS configuration.
Update your domain's DNS A record to point to the assigned IP address.
Create an HTTPRoute to define routing rules from the Gateway to your backend service.
Create the HTTPRoute manifest file.
Add the following configuration. Replace myapp.example.com with your domain name.
Save and close the file.
For path-based routing to multiple services, add additional rules:
Apply the HTTPRoute manifest.
Verify the TLS certificate status.
The certificate may take a few minutes to provision. Wait until the READY column shows True.
After applying all Kubernetes manifests, verify that your application functions correctly on VKE.
Monitor the deployment progress.
The command displays real-time pod status updates. Wait until all pods show STATUS as Running and READY shows the expected ratio (e.g., 1/1). Press Ctrl + C to exit watch mode.
Check the pod logs to verify the application started correctly.
Verify that the Service is routing traffic to the pods.
The output displays the pod IP addresses and ports that the Service routes traffic to. The number of endpoints should match your replica count.
Test internal service connectivity from within the cluster.
This command creates a temporary pod that sends an HTTP request to your service. The output displays the HTTP response, confirming internal networking functions correctly.
Verify the Gateway external IP address.
Note the IP address assigned to the Gateway.
Test external connectivity through the Gateway using your domain name.
Replace myapp.example.com with your actual domain. The output displays your application's HTTP response, confirming external access works correctly with TLS encryption.
Monitor HPA behavior under load.
The HPA displays current CPU and memory utilization alongside current and desired replica counts. The autoscaler adjusts replicas automatically based on the metrics.
After validating that the application is running correctly on Vultr Kubernetes Engine (VKE), perform a controlled cut over to move production traffic from Amazon ECS to the Kubernetes-based deployment.
After traffic is fully served by VKE and the application is stable, scale ECS services to zero and keep the existing ECS resources available for rollback if needed.
Update your continuous integration and deployment pipelines to deploy workloads to Vultr Kubernetes Engine (VKE) instead of Amazon ECS. This change replaces ECS service updates and task definition revisions with Kubernetes-native deployment workflows.
Replace the ECS service update command with a Kubernetes rollout.
The kubectl set image command updates the container image for the Deployment, while kubectl rollout status monitors the rolling update until all pods are running the new version.
Configure access to the VKE cluster in your CI/CD environment.
KUBECONFIG environment variable.CI/CD implementations vary by platform and workflow. This example demonstrates one automated deployment approach. Adjust the steps as required to match your CI/CD tooling, security model, and environment.
Depending on your application requirements, you may also reference the following topics, which are intentionally out of scope for this walkthrough:
Container Images: Migrating container images from AWS ECR to Vultr Container Registry. Refer to the Vultr Container Registry migration guide.
Persistent Storage: Configuring PersistentVolumeClaims using Vultr Block Storage or Vultr File System. See the VKE PVC guide.
Databases: Migrating database workloads from AWS RDS to Vultr Managed Databases. Refer to the MySQL migration guide or the PostgreSQL migration guide.
You have successfully migrated containerized workloads from Amazon ECS to Vultr Kubernetes Engine by converting ECS task definitions into Kubernetes Deployments, replicating service discovery and load balancing, migrating configuration and secrets, and updating CI/CD pipelines. VKE provides a fully managed, standards-based Kubernetes platform that reduces vendor lock-in while offering flexible networking and production-ready orchestration. For advanced configurations and operational best practices, refer to the official Vultr Kubernetes Engine documentation.
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