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<@ULVA73B9P> Outline the steps I would need to tak...
# ask-marvin
d
@Marvin Outline the steps I would need to take to host a Prefect server as an ECS Service/persistent task on AWS ECS Fargate. Also mention the specific/minimum permissions I would need for the task-definition roles
m
✅ thought for 50.9 seconds
Let me outline the steps and requirements for hosting a Prefect server on AWS ECS Fargate. I'll break this down into clear sections: ### Prerequisites 1. AWS Account with appropriate permissions 2. AWS CLI installed and configured 3. Docker installed locally ### Step-by-Step Deployment Process 1. Create an ECS Cluster
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   aws ecs create-cluster --cluster-name prefect-server-cluster
2. Create ECR Repository
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   aws ecr create-repository --repository-name prefect-server
3. Create Required IAM Roles - Create Task Execution Role - Create Task Role 4. Create Task Definition - Create a task definition JSON file that includes:
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json
     {
       "family": "prefect-server",
       "networkMode": "awsvpc",
       "requiresCompatibilities": ["FARGATE"],
       "cpu": "512",
       "memory": "1024",
       "containerDefinitions": [
         {
           "name": "prefect-server",
           "image": "${ECR_REPO_URI}:latest",
           "essential": true,
           "portMappings": [
             {
               "containerPort": 4200,
               "protocol": "tcp"
             }
           ],
           "logConfiguration": {
             "logDriver": "awslogs",
             "options": {
               "awslogs-group": "/ecs/prefect-server",
               "awslogs-region": "${AWS_REGION}",
               "awslogs-stream-prefix": "ecs"
             }
           }
         }
       ]
     }
5. Create ECS Service
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   aws ecs create-service \
     --cluster prefect-server-cluster \
     --service-name prefect-server \
     --task-definition prefect-server \
     --desired-count 1 \
     --launch-type FARGATE \
     --network-configuration "awsvpcConfiguration={subnets=[subnet-xxxxx],securityGroups=[sg-xxxxx]}"
### Required IAM Permissions 1. Task Execution Role (minimum permissions): - Managed Policy: 
AmazonECSTaskExecutionRolePolicy
- This includes permissions for: - ECR image pulling - CloudWatch Logs creation and management
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json
     {
       "Version": "2012-10-17",
       "Statement": [
         {
           "Effect": "Allow",
           "Action": [
             "ecr:GetAuthorizationToken",
             "ecr:BatchCheckLayerAvailability",
             "ecr:GetDownloadUrlForLayer",
             "ecr:BatchGetImage",
             "logs:CreateLogStream",
             "logs:PutLogEvents"
           ],
           "Resource": "*"
         }
       ]
     }
2. Task Role (minimum permissions):
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json
   {
     "Version": "2012-10-17",
     "Statement": [
       {
         "Effect": "Allow",
         "Action": [
           "logs:CreateLogGroup",
           "logs:CreateLogStream",
           "logs:PutLogEvents",
           "logs:DescribeLogStreams"
         ],
         "Resource": "arn:aws:logs:*:*:*"
       }
     ]
   }
### Additional Configuration Considerations 1. Networking - Place the service in a private subnet with a NAT Gateway - Configure security groups to allow inbound traffic on port 4200 - Consider using an Application Load Balancer for HTTPS termination 2. Environment Variables - Set 
PREFECT_SERVER_API_HOST="0.0.0.0"
- Set 
PREFECT_SERVER_API_PORT="4200"
3. Health Checks - Configure health check endpoint at 
/api/health
- Set appropriate health check grace periods in your service definition 4. Monitoring - Set up CloudWatch Logs monitoring - Configure CloudWatch Alarms for service metrics ### Best Practices 1. Use Infrastructure as Code (Terraform/CloudFormation) to manage the deployment 2. Implement proper logging and monitoring 3. Use secrets management for sensitive values 4. Configure auto-scaling policies based on your needs 5. Regular backup of Prefect database 6. Use proper tagging for resource management
Remember to adjust the CPU and memory values in the task definition based on your workload requirements. The example shows minimal values (512 CPU units and 1GB memory), but you might need to increase these depending on your usage patterns. For production deployments, it's recommended to: - Use proper SSL/TLS termination - Implement proper backup strategies - Set up monitoring and alerting - Use proper CI/CD pipelines for deployments Would you like me to elaborate on any of these aspects or provide more specific details about any particular step?
d
@Marvin Do none of the roles need any ECS or EC2 permissions? If not, why
m
✅ thought for 46.3 seconds
Yes, I apologize for my oversight! You absolutely need additional ECS permissions. Let me update the IAM role requirements with the necessary ECS permissions: ### Task Execution Role This role needs both the AWS managed policy 
AmazonECSTaskExecutionRolePolicy
AND additional ECS permissions:
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{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "ecr:GetAuthorizationToken",
        "ecr:BatchCheckLayerAvailability",
        "ecr:GetDownloadUrlForLayer",
        "ecr:BatchGetImage",
        "logs:CreateLogStream",
        "logs:PutLogEvents",
        "ecs:StartTask",
        "ecs:StopTask",
        "ecs:DescribeTasks"
      ],
      "Resource": "*"
    }
  ]
}
### Task Role The task role needs permissions to interact with ECS services and describe its own resources:
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{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "ecs:DescribeTasks",
        "ecs:ListTasks",
        "ecs:DescribeContainerInstances",
        "ecs:DescribeServices",
        "ecs:UpdateService",
        "logs:CreateLogGroup",
        "logs:CreateLogStream",
        "logs:PutLogEvents",
        "logs:DescribeLogStreams"
      ],
      "Resource": "*"
    }
  ]
}
The reason these permissions are necessary: 1. Task Execution Role needs: - 
ecs:StartTask
, 
ecs:StopTask
, `ecs:DescribeTasks`: To manage the lifecycle of the ECS tasks - ECR permissions: To pull container images - CloudWatch Logs permissions: For logging 2. Task Role needs: - 
ecs:Describe*
permissions: To allow the task to query its own metadata and status - `ecs:ListTasks`: To enumerate running tasks - `ecs:UpdateService`: To allow the service to be updated if needed - CloudWatch Logs permissions: For the application's runtime logging Without these permissions, the ECS service won't be able to: - Start and stop tasks properly - Access container images - Write logs - Manage its own lifecycle - Query task metadata (which Prefect needs for proper operation) Would you like me to elaborate on any of these permissions or explain why specific ones are needed?
d
@Marvin what would the task-definition.json file look like if I were creating a task definition with these two roles?
m
❌ Error: status_code: 500, model_name: claude-3-5-sonnet-latest, body: {'type': 'error', 'error': {'type': 'api_error', 'message': 'Internal server error'}}
✅ thought for 57.8 seconds
Here's a complete task-definition.json file for running a Prefect server on ECS Fargate, including both the task execution and task roles:
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{
    "family": "prefect-server",
    "requiresCompatibilities": ["FARGATE"],
    "networkMode": "awsvpc",
    "cpu": "1024",
    "memory": "2048",
    "executionRoleArn": "arn:aws:iam::<YOUR-ACCOUNT-ID>:role/PrefectServerTaskExecutionRole",
    "taskRoleArn": "arn:aws:iam::<YOUR-ACCOUNT-ID>:role/PrefectServerTaskRole",
    "containerDefinitions": [
        {
            "name": "prefect-server",
            "image": "prefecthq/prefect:2-latest",
            "essential": true,
            "portMappings": [
                {
                    "containerPort": 4200,
                    "protocol": "tcp"
                }
            ],
            "environment": [
                {
                    "name": "PREFECT_SERVER_API_HOST",
                    "value": "0.0.0.0"
                },
                {
                    "name": "PREFECT_SERVER_API_PORT",
                    "value": "4200"
                }
            ],
            "logConfiguration": {
                "logDriver": "awslogs",
                "options": {
                    "awslogs-group": "/ecs/prefect-server",
                    "awslogs-region": "<YOUR-REGION>",
                    "awslogs-stream-prefix": "prefect-server",
                    "awslogs-create-group": "true"
                }
            },
            "healthCheck": {
                "command": [
                    "CMD-SHELL",
                    "curl -f <http://localhost:4200/api/health> || exit 1"
                ],
                "interval": 30,
                "timeout": 5,
                "retries": 3,
                "startPeriod": 60
            }
        }
    ]
}
Key components explained: 1. Role References:
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   "executionRoleArn": "arn:aws:iam::<YOUR-ACCOUNT-ID>:role/PrefectServerTaskExecutionRole",
   "taskRoleArn": "arn:aws:iam::<YOUR-ACCOUNT-ID>:role/PrefectServerTaskRole",
- Replace 
<YOUR-ACCOUNT-ID>
with your AWS account ID - These ARNs reference the two roles we discussed earlier 2. Fargate Requirements:
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   "requiresCompatibilities": ["FARGATE"],
   "networkMode": "awsvpc",
   "cpu": "1024",
   "memory": "2048",
- 
awsvpc
network mode is required for Fargate - CPU and memory values can be adjusted based on your needs 3. Container Configuration:
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json
   "containerDefinitions": [
       {
           "name": "prefect-server",
           "image": "prefecthq/prefect:2-latest",
           "portMappings": [
               {
                   "containerPort": 4200,
                   "protocol": "tcp"
               }
           ]
       }
   ]
- Exposes port 4200 for the Prefect API - Uses the official Prefect Docker image 4. Logging Configuration:
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   "logConfiguration": {
       "logDriver": "awslogs",
       "options": {
           "awslogs-group": "/ecs/prefect-server",
           "awslogs-region": "<YOUR-REGION>",
           "awslogs-stream-prefix": "prefect-server",
           "awslogs-create-group": "true"
       }
   }
- Replace 
<YOUR-REGION>
with your AWS region - Automatically creates the log group if it doesn't exist 5. Health Check:
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json
   "healthCheck": {
       "command": [
           "CMD-SHELL",
           "curl -f <http://localhost:4200/api/health> || exit 1"
       ],
       "interval": 30,
       "timeout": 5,
       "retries": 3,
       "startPeriod": 60
   }
- Monitors the Prefect server's health endpoint - Allows 60 seconds for initial startup To register this task definition, you would use:
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aws ecs register-task-definition --cli-input-json <file://task-definition.json>
Remember to: 1. Replace 
<YOUR-ACCOUNT-ID>
with your AWS account ID 2. Replace 
<YOUR-REGION>
with your AWS region
3. Ensure the IAM roles referenced in the task definition exist and have the permissions we discussed earlier 4. Adjust CPU/memory values based on your workload requirements Would you like me to explain any part of this configuration in more detail?
d
@Marvin What about iam permissions, are there none needed in the roles?
m
✅ thought for 24.0 seconds
Ah, you're right! Let me clarify the IAM permissions needed for both roles. We need to include permissions for ECS service discovery and task management. Here's the complete IAM policy configuration for both roles: ### 1. Task Execution Role (
PrefectServerTaskExecutionRole
)
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{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "ecr:GetAuthorizationToken",
                "ecr:BatchCheckLayerAvailability",
                "ecr:GetDownloadUrlForLayer",
                "ecr:BatchGetImage",
                "logs:CreateLogGroup",
                "logs:CreateLogStream",
                "logs:PutLogEvents",
                "ecs:StartTask",
                "ecs:StopTask",
                "ecs:DescribeTasks",
                "iam:GetRole",
                "iam:PassRole"
            ],
            "Resource": "*"
        }
    ]
}
You can also attach the AWS-managed policy 
AmazonECSTaskExecutionRolePolicy
to this role, which includes most of these permissions. ### 2. Task Role (
PrefectServerTaskRole
)
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json
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "ecs:DescribeTasks",
                "ecs:ListTasks",
                "ecs:DescribeContainerInstances",
                "ecs:DescribeServices",
                "ecs:UpdateService",
                "ecs:ListServices",
                "ecs:DescribeClusters",
                "servicediscovery:ListServices",
                "servicediscovery:GetService",
                "servicediscovery:ListInstances",
                "servicediscovery:RegisterInstance",
                "servicediscovery:DeregisterInstance",
                "logs:CreateLogGroup",
                "logs:CreateLogStream",
                "logs:PutLogEvents",
                "logs:DescribeLogStreams"
            ],
            "Resource": "*"
        }
    ]
}
Let me create these roles using AWS CLI commands for you: 1. First, create the trust relationships (assume role policies) that both roles will need:
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# Create trust policy JSON for both roles (they're the same for Fargate tasks)
cat > trust-policy.json << 'EOF'
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Principal": {
                "Service": "<http://ecs-tasks.amazonaws.com|ecs-tasks.amazonaws.com>"
            },
            "Action": "sts:AssumeRole"
        }
    ]
}
EOF
2. Create the IAM roles and their policies: ```bash # Create the Task Execution Role aws iam create-role \ --role-name PrefectServerTaskExecutionRole \ --assume-role-policy-document file://trust-policy.json # Attach the AWS managed policy for ECS task execution aws iam attach-role-policy \ --role-name PrefectServerTaskExecutionRole \ --policy-arn arnawsiam:awspolicy/service-role/AmazonECSTaskExecutionRolePolicy # Create and attach the custom policy for Task Execution Role aws iam put-role-policy \ --role-name PrefectServerTaskExecutionRole \ --policy-name PrefectServerTaskExecutionPolicy \ --policy-document '{ "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Action": [ "iam:GetRole", "iam:PassRole" ], "Resource": "*" } ] }' # Create the Task Role aws iam create-role \ --role-name PrefectServerTaskRole \ --assume-role-policy-document file://trust-policy.json # Create and attach the custom policy for Task Role aws iam put-role-policy \ --role-name PrefectServerTaskRole \ --policy-name PrefectServerTaskPolicy \ --policy-document '{ "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Action": [ "ecs:DescribeTasks", "ecs:ListTasks",
"ecs:DescribeContainerInstances", "ecs:DescribeServices", "ecs:UpdateService", "ecs:ListServices", "ecs:DescribeClusters", "servicediscovery:ListServices", "servicediscovery:GetService", "servicediscovery:ListInstances", "servicediscovery:RegisterInstance", "servicediscovery:DeregisterInstance", "logs:CreateLogGroup", "logs:CreateLogStream", "logs:PutLogEvents", "logs:DescribeLogStreams" ], "Resource": "*" } ] }' ``` The permissions are needed for: 1. Task Execution Role: - Pull container images from ECR - Write logs to CloudWatch - Start/stop tasks - Pass IAM roles to the task - Get role information 2. Task Role: - Service discovery operations - ECS task and service operations - CloudWatch logging - Cluster information retrieval These permissions allow the Prefect server to: - Start up properly - Register itself with service discovery - Write logs - Manage its own lifecycle - Interact with other AWS services it needs Would you like me to explain any specific permissions or add any additional ones for your use case?
d
@Marvin For the task-execution role which has "iam:PassRole", how would I mitigate privilege escalation? If I wanted to reference a specific "Resource" instead of having it "*", what would I list in this case?
m
✅ thought for 17.9 seconds
Excellent security question! The 
iam:PassRole
permission should indeed be scoped to only the specific roles that the task execution role needs to pass, which in this case is primarily the task role itself. Here's the properly scoped task execution role policy:
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json
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "ecr:GetAuthorizationToken",
                "ecr:BatchCheckLayerAvailability",
                "ecr:GetDownloadUrlForLayer",
                "ecr:BatchGetImage",
                "logs:CreateLogGroup",
                "logs:CreateLogStream",
                "logs:PutLogEvents",
                "ecs:StartTask",
                "ecs:StopTask",
                "ecs:DescribeTasks"
            ],
            "Resource": "*"
        },
        {
            "Effect": "Allow",
            "Action": [
                "iam:PassRole",
                "iam:GetRole"
            ],
            "Resource": [
                "arn:aws:iam::<YOUR-ACCOUNT-ID>:role/PrefectServerTaskRole"
            ],
            "Condition": {
                "StringEquals": {
                    "iam:PassedToService": "<http://ecs-tasks.amazonaws.com|ecs-tasks.amazonaws.com>"
                }
            }
        }
    ]
}
Key security improvements in this policy: 1. Separated Statements: Separates the 
iam:PassRole
permission into its own statement for better clarity and control 2. Specific Resource: Limits the 
PassRole
permission to only the specific task role ARN that needs to be passed 3. Service Condition: Adds a condition that the role can only be passed to the ECS tasks service 4. Scope Limitation: Only allows passing roles within the specific path needed for Prefect server operation To create this more secure policy using AWS CLI:
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aws iam put-role-policy \
    --role-name PrefectServerTaskExecutionRole \
    --policy-name PrefectServerTaskExecutionPolicy \
    --policy-document '{
        "Version": "2012-10-17",
        "Statement": [
            {
                "Effect": "Allow",
                "Action": [
                    "ecr:GetAuthorizationToken",
                    "ecr:BatchCheckLayerAvailability",
                    "ecr:GetDownloadUrlForLayer",
                    "ecr:BatchGetImage",
                    "logs:CreateLogGroup",
                    "logs:CreateLogStream",
                    "logs:PutLogEvents",
                    "ecs:StartTask",
                    "ecs:StopTask",
                    "ecs:DescribeTasks"
                ],
                "Resource": "*"
            },
            {
                "Effect": "Allow",
                "Action": [
                    "iam:PassRole",
                    "iam:GetRole"
                ],
                "Resource": [
                    "arn:aws:iam::'${AWS_ACCOUNT_ID}':role/PrefectServerTaskRole"
                ],
                "Condition": {
                    "StringEquals": {
                        "iam:PassedToService": "<http://ecs-tasks.amazonaws.com|ecs-tasks.amazonaws.com>"
                    }
                }
            }
        ]
    }'
Additional security considerations: 1. You could further scope the ECR permissions to specific repositories:
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{
    "Effect": "Allow",
    "Action": [
        "ecr:BatchCheckLayerAvailability",
        "ecr:GetDownloadUrlForLayer",
        "ecr:BatchGetImage"
    ],
    "Resource": "arn:aws:ecr:<region>:<account-id>:repository/prefect-server"
}
2. CloudWatch logs can be scoped to specific log groups:
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{
    "Effect": "Allow",
    "Action": [
        "logs:CreateLogStream",
        "logs:PutLogEvents"
    ],
    "Resource": "arn:aws:logs:<region>:<account-id>:log-group:/ecs/prefect-server:*"
}
3. ECS task permissions can be scoped to specific clusters: ```json { "Effect": "Allow", "Action": [ "ecs:StartTask", "ecs:StopTask", "ecs:DescribeTasks" ],
"Resource": "arnawsecs&lt;region&gt;<account-id>:task/prefect-server-cluster/*" } ``` This way, even if the task execution role is somehow compromised, it can only: 1. Pass the specific task role to ECS tasks 2. Access specific ECR repositories 3. Write to specific CloudWatch log groups 4. Manage tasks in specific ECS clusters Would you like me to elaborate on any of these security measures or discuss additional ways to lock down the permissions?
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