Troubleshooting

Troubleshooting LabLink Deployments

Troubleshooting workflow

Starting in local repo folder lablink/lablink-allocator

1. Initialize allocator terraform state locally using AWS CLI

terraform init -backend-config=backend-dev.hcl -reconfigure

2. Plan terraform resources

AWS_PROFILE=711387140753_PowerUserAccess terraform plan -var="resource_suffix=dev"

Check resources. 🔑 Create tls_private_key.lablink_key – a new 4096-bit RSA key

aws_key_pair.lablink_key_pair – named lablink-key-dev

aws_security_group.allow_http – named allow_http_dev, open ports 22 and 80

aws_instance.lablink_allocator_server – tagged as lablink_allocator_server_dev, AMI ami-00c257e12d6828491, type t2.micro

aws_eip.lablink_allocator_ip – elastic IP with tag lablink_allocator_ip_dev

aws_eip_association.lablink_allocator_ip_assoc – binds the EIP to the instance

✅ Outputs ec2_key_name = "lablink-key-dev"

ec2_public_ip = dynamically assigned, known after apply

private_key_pem = sensitive output (good practice)

3. Apply changes

terraform apply -var="resource_suffix=dev"

4. Get pem key for SSH into EC2 instance

terraform output -raw private_key_pem > ~/lablink-key-dev.pem

chmod 600 ~/lablink-key-dev.pem

5. Check admin website at "<ec2_public_ip>/admin" or ssh

ssh -i ~/lablink-key-dev.pem ubuntu@<ec2_public_ip>

6. When you are ready, destroy resources

terraform destroy -var="resource_suffix=dev"

7. If you started any VMs, you can terminate those using the "Terraform Destroy" github action workflow using "Run workflow" at https://github.com/talmolab/lablink/actions/workflows/lablink-allocator-destroy.yml

Docker Permission Error

permission denied while trying to connect to the Docker daemon socket

Solution:

sudo usermod -aG docker $USER
newgrp docker

Or use sudo docker ... commands.

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Can't SSH to Instance

• Ensure correct PEM key is used
• Instance must have port 22 open in its security group
• Check EC2 public IP from Terraform output

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Flask Server Not Responding

• Check container logs:

  sudo docker ps
  sudo docker logs <container_id>
  cat /var/log/cloud-init-output.log

• Interact with container

  sudo docker exec -it <container_id> /bin/bash 
  

• Test with:

  curl localhost:80

You should see the HTML page for the Flask app.

• Ping server

  nc -vz <ec2_public_ip> 80
  

• Check http vs https

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VM Not Spawning

• Check the allocator container logs
• Verify AWS credentials (access key, secret, token) are passed into the container
• Confirm that terraform apply was triggered inside the container