1. 新建一个EC2 Launch Template，将实例类型更改为t4g.medium，并指定所需的AMI、存储和其他参数。

2. 在ECS中创建一个任务定义，并将EC2 Launch Template指定为默认启动模板，如下所示：

{
 "family": "my-task-def",
 "containerDefinitions": [
   {
     "name": "my-container",
     "image": "my-repo/my-image",
     "cpu": 256,
     "memory": 512
    }
 ],
 "taskRoleArn": "arn:aws:iam::123456789012:role/my-task-role",
 "executionRoleArn": "arn:aws:iam::123456789012:role/my-execution-role",
 "networkMode": "awsvpc",
 "requiresCompatibilities": ["EC2"],
 "placementConstraints": [
   {
     "type": "distinctInstance"
   }
 ],
 "launchType": "EC2",
 "cpu": "256",
 "memory": "512",
 "tags": [
   {
     "key": "my-key",
     "value": "my-value"
   }
 ],
 "platformVersion": "LATEST",
 "volumes": [],
 "defaultContainer": [
   {
     "image": "my-repo/my-image",
     "name": "my-container",
     "cpu": 256,
     "memory": 512,
     "essential": true,
     "portMappings": [
       {
         "hostPort": 5000,
         "containerPort": 80
       }
     ]
   }
 ],
 "requiresAttributes": [
   {
     "name": "ecs.capability.execution-role-awslogs",
     "value": "true"
   },
   {
     "name": "com.amazonaws.ecs.capability.ecr-auth",
     "value": "true"
   }
 ]
}

3. 将任务提交到ECS群集。

在完成这些步骤后，您的ECS任务应该能够在t4g.medium实例上启动和运行。