Valheim Dedicated Server on AWS ECS Fargate

Terraform infrastructure to deploy a Valheim dedicated server on AWS ECS Fargate with EFS persistent storage and S3 backups.

Architecture

• ECS Fargate - Serverless container compute (2 vCPU, 4GB RAM)
• EFS - Persistent storage for world saves
• S3 - Backup storage with 30-day lifecycle
• CloudWatch - Container logs
• VPC - Isolated network with public IP

Prerequisites

• AWS CLI configured (aws configure)
• Terraform >= 1.0
• AWS account with IAM permissions for ECS, EFS, S3, VPC

Quick Start

1. Clone and initialize:

git clone <your-repo>
cd valheim-ecs
terraform init

2. Configure (optional): Edit terraform.tfvars:

server_name = "4mp3d's Server"
world_name = "Dedicated"
password = "Eriksson"
aws_region = "us-east-1"

3. Deploy:

terraform plan
terraform apply

4. Get server IP:

aws ecs describe-tasks
--cluster valheim-cluster
--tasks $(aws ecs list-tasks --cluster valheim-cluster --query 'taskArns[0]' --output text)
--query 'tasks[0].attachments[0].details[?name==networkInterfaceId].value'
--output text | xargs aws ec2 describe-network-interfaces
--network-interface-ids | grep PublicIp

5. Connect in Valheim:

• IP: YOUR_IP:2456
• Password: Eriksson

Server Configuration

Setting	Value	Description
Server Name	4mp3d's Server	Display name in server list
World	Dedicated	World save name
Password	Eriksson	Connection password
Save Interval	30 min	Auto-save frequency
Backups	3 rolling	Every 2 hours, kept 6 hours
Modifiers	Raids: Much Less	Reduced raid frequency

Costs

~$50-60/month running 24/7:

• ECS Fargate (2 vCPU, 4GB): ~$45
• EFS (10GB): ~$3
• S3 backups: ~$0.50
• Data transfer: ~$5-10

Management Commands

View logs:

aws logs tail /ecs/valheim --follow

Stop server (keeps data):

aws ecs update-service --cluster valheim-cluster --service valheim-server --desired-count 0

Start server:

aws ecs update-service --cluster valheim-cluster --service valheim-server --desired-count 1

Download backup:

aws s3 sync s3://$(terraform output -raw backup_bucket)/backups/ ./local-backups/

Destroy

⚠️ Warning: This deletes your world data in EFS. Back up first!

terraform destroy

Troubleshooting

Issue	Solution
"Wrong password"	Check SERVER_PASS env var in task definition
Container keeps stopping	Check CloudWatch logs: aws logs tail /ecs/valheim
Can't connect	Verify security group allows UDP 2456-2458
No server in browser	Wait 2-3 minutes for Steam registration

Files

• main.tf - Main infrastructure (VPC, ECS, EFS, S3)
• variables.tf - Input variables
• terraform.tfvars - User configuration

Credits

• Docker image: lloesche/valheim-server