aws-ec2

AWS EC2

部署和管理 Amazon EC2 计算实例，以承载生产、预发布和开发工作负载。

适用场景

• 启动新的计算实例以托管应用
• 构建黄金 AMI，实现一致的部署
• 在负载均衡器后配置自动扩缩组
• 将工作负载迁移到 Spot 实例以节省成本
• 排查实例连接、性能或启动故障
• 创建启动模板，实现可重复的基础设施部署

前提条件

• 已安装并配置 AWS CLI v2（aws configure）
• IAM 权限：ec2:*、autoscaling:*、elasticloadbalancing:*、iam:PassRole
• 已有包含子网的 VPC（参见 aws-vpc）
• 已创建 SSH 密钥对（aws ec2 create-key-pair --key-name my-key --query 'KeyMaterial' --output text > my-key.pem）

实例类型选择指南

类别	类型	用例
通用型	t3、t3a、m6i、m7g	Web 服务器、小型数据库、开发/测试
计算优化型	c6i、c7g	批处理、媒体编码、机器学习推理
内存优化型	r6i、r7g、x2idn	内存缓存、大型数据库
存储优化型	i3、i4i、d3	数据仓库、分布式文件系统
加速型	p4d、g5、inf2	机器学习训练、GPU 渲染、推理
突增型	t3.micro-t3.2xlarge	稳定负载较低、偶尔需要突增的场景

启动实例

# Launch a production web server
aws ec2 run-instances \
  --image-id ami-0abcdef1234567890 \
  --instance-type t3.medium \
  --key-name my-key \
  --security-group-ids sg-12345678 \
  --subnet-id subnet-12345678 \
  --iam-instance-profile Name=EC2AppProfile \
  --metadata-options "HttpTokens=required,HttpEndpoint=enabled" \
  --block-device-mappings '[{
    "DeviceName": "/dev/xvda",
    "Ebs": {
      "VolumeSize": 30,
      "VolumeType": "gp3",
      "Iops": 3000,
      "Throughput": 125,
      "Encrypted": true
    }
  }]' \
  --tag-specifications 'ResourceType=instance,Tags=[
    {Key=Name,Value=web-server-01},
    {Key=Environment,Value=production},
    {Key=Team,Value=platform}
  ]' \
  --user-data file://userdata.sh

# Launch with IMDSv2 required (security best practice)
aws ec2 run-instances \
  --image-id ami-0abcdef1234567890 \
  --instance-type t3.micro \
  --metadata-options "HttpTokens=required,HttpPutResponseHopLimit=1,HttpEndpoint=enabled" \
  --tag-specifications 'ResourceType=instance,Tags=[{Key=Name,Value=secure-instance}]'

用户数据脚本

#!/bin/bash
# userdata.sh - Bootstrap a web server on Amazon Linux 2023
set -euxo pipefail

# System updates
dnf update -y

# Install and start web server
dnf install -y nginx
systemctl enable nginx
systemctl start nginx

# Install CloudWatch agent
dnf install -y amazon-cloudwatch-agent
/opt/aws/amazon-cloudwatch-agent/bin/amazon-cloudwatch-agent-ctl \
  -a fetch-config -m ec2 \
  -s -c ssm:AmazonCloudWatch-linux

# Install CodeDeploy agent
dnf install -y ruby wget
cd /home/ec2-user
wget https://aws-codedeploy-us-east-1.s3.us-east-1.amazonaws.com/latest/install
chmod +x ./install
./install auto

# Signal CloudFormation (if launched via CFN)
# /opt/aws/bin/cfn-signal -e $? --stack ${AWS::StackName} --resource ASG --region ${AWS::Region}

启动模板

# Create a launch template with full configuration
aws ec2 create-launch-template \
  --launch-template-name web-server-template \
  --version-description "v1 - AL2023 with nginx" \
  --launch-template-data '{
    "ImageId": "ami-0abcdef1234567890",
    "InstanceType": "t3.medium",
    "KeyName": "my-key",
    "SecurityGroupIds": ["sg-12345678"],
    "IamInstanceProfile": {"Name": "EC2AppProfile"},
    "MetadataOptions": {
      "HttpTokens": "required",
      "HttpEndpoint": "enabled"
    },
    "BlockDeviceMappings": [{
      "DeviceName": "/dev/xvda",
      "Ebs": {
        "VolumeSize": 30,
        "VolumeType": "gp3",
        "Encrypted": true
      }
    }],
    "TagSpecifications": [{
      "ResourceType": "instance",
      "Tags": [
        {"Key": "Environment", "Value": "production"},
        {"Key": "ManagedBy", "Value": "launch-template"}
      ]
    }],
    "Monitoring": {"Enabled": true},
    "UserData": "'"$(base64 -w0 userdata.sh)"'"
  }'

# Create a new version of the launch template
aws ec2 create-launch-template-version \
  --launch-template-name web-server-template \
  --source-version 1 \
  --version-description "v2 - updated AMI" \
  --launch-template-data '{"ImageId": "ami-0newami1234567890"}'

# Set the default version
aws ec2 modify-launch-template \
  --launch-template-name web-server-template \
  --default-version 2

自动扩缩组

# Create ASG with mixed instances (on-demand + spot)
aws autoscaling create-auto-scaling-group \
  --auto-scaling-group-name web-asg \
  --mixed-instances-policy '{
    "LaunchTemplate": {
      "LaunchTemplateSpecification": {
        "LaunchTemplateName": "web-server-template",
        "Version": "$Default"
      },
      "Overrides": [
        {"InstanceType": "t3.medium"},
        {"InstanceType": "t3a.medium"},
        {"InstanceType": "m5.large"}
      ]
    },
    "InstancesDistribution": {
      "OnDemandBaseCapacity": 2,
      "OnDemandPercentageAboveBaseCapacity": 25,
      "SpotAllocationStrategy": "capacity-optimized"
    }
  }' \
  --min-size 2 --max-size 10 --desired-capacity 4 \
  --vpc-zone-identifier "subnet-aaa,subnet-bbb" \
  --target-group-arns "arn:aws:elasticloadbalancing:us-east-1:123456789012:targetgroup/web-tg/abc123" \
  --health-check-type ELB \
  --health-check-grace-period 300 \
  --tags '[
    {"Key":"Name","Value":"web-asg","PropagateAtLaunch":true},
    {"Key":"Environment","Value":"production","PropagateAtLaunch":true}
  ]'

# Create target tracking scaling policy (target 60% CPU)
aws autoscaling put-scaling-policy \
  --auto-scaling-group-name web-asg \
  --policy-name cpu-target-tracking \
  --policy-type TargetTrackingScaling \
  --target-tracking-configuration '{
    "PredefinedMetricSpecification": {
      "PredefinedMetricType": "ASGAverageCPUUtilization"
    },
    "TargetValue": 60.0,
    "ScaleInCooldown": 300,
    "ScaleOutCooldown": 60
  }'

# Create scheduled scaling for known traffic patterns
aws autoscaling put-scheduled-update-group-action \
  --auto-scaling-group-name web-asg \
  --scheduled-action-name scale-up-morning \
  --recurrence "0 8 * * MON-FRI" \
  --min-size 4 --max-size 20 --desired-capacity 8

aws autoscaling put-scheduled-update-group-action \
  --auto-scaling-group-name web-asg \
  --scheduled-action-name scale-down-evening \
  --recurrence "0 20 * * MON-FRI" \
  --min-size 2 --max-size 10 --desired-capacity 2

Spot 实例

# Request Spot instances
aws ec2 request-spot-instances \
  --spot-price "0.05" \
  --instance-count 3 \
  --type "one-time" \
  --launch-specification '{
    "ImageId": "ami-0abcdef1234567890",
    "InstanceType": "c5.xlarge",
    "KeyName": "my-key",
    "SecurityGroupIds": ["sg-12345678"],
    "SubnetId": "subnet-12345678"
  }'

# Check current Spot prices
aws ec2 describe-spot-price-history \
  --instance-types t3.medium t3a.medium m5.large \
  --availability-zone us-east-1a \
  --product-descriptions "Linux/UNIX" \
  --start-time "$(date -u +%Y-%m-%dT%H:%M:%SZ)" \
  --query "SpotPriceHistory[].{Type:InstanceType,Price:SpotPrice,AZ:AvailabilityZone}" \
  --output table

# Create a Spot Fleet request
aws ec2 request-spot-fleet \
  --spot-fleet-request-config '{
    "IamFleetRole": "arn:aws:iam::123456789012:role/aws-ec2-spot-fleet-role",
    "TargetCapacity": 10,
    "SpotPrice": "0.10",
    "AllocationStrategy": "capacityOptimized",
    "LaunchSpecifications": [
      {"ImageId": "ami-xxx", "InstanceType": "c5.xlarge", "SubnetId": "subnet-aaa"},
      {"ImageId": "ami-xxx", "InstanceType": "c5a.xlarge", "SubnetId": "subnet-bbb"}
    ]
  }'

AMI 管理

# Create an AMI from a running instance
aws ec2 create-image \
  --instance-id i-0abc123def456 \
  --name "web-server-$(date +%Y%m%d)" \
  --description "Web server golden AMI" \
  --no-reboot \
  --tag-specifications 'ResourceType=image,Tags=[
    {Key=Name,Value=web-server-golden},
    {Key=Version,Value=2026.03.24}
  ]'

# Copy AMI to another region for disaster recovery
aws ec2 copy-image \
  --source-image-id ami-0abcdef1234567890 \
  --source-region us-east-1 \
  --region us-west-2 \
  --name "web-server-dr-copy"

# Deregister old AMIs and delete associated snapshots
aws ec2 deregister-image --image-id ami-old123
aws ec2 delete-snapshot --snapshot-id snap-old123

# Share AMI with another AWS account
aws ec2 modify-image-attribute \
  --image-id ami-0abcdef1234567890 \
  --launch-permission "Add=[{UserId=987654321098}]"

实例管理

# List running instances with key details
aws ec2 describe-instances \
  --filters "Name=instance-state-name,Values=running" \
  --query "Reservations[].Instances[].{ID:InstanceId,Type:InstanceType,IP:PrivateIpAddress,Name:Tags[?Key=='Name']|[0].Value,State:State.Name}" \
  --output table

# Stop and start instances
aws ec2 stop-instances --instance-ids i-0abc123def456
aws ec2 start-instances --instance-ids i-0abc123def456

# Resize an instance (stop first)
aws ec2 stop-instances --instance-ids i-0abc123def456
aws ec2 wait instance-stopped --instance-ids i-0abc123def456
aws ec2 modify-instance-attribute \
  --instance-id i-0abc123def456 \
  --instance-type '{"Value": "t3.large"}'
aws ec2 start-instances --instance-ids i-0abc123def456

# Get console output for debugging boot issues
aws ec2 get-console-output --instance-id i-0abc123def456

# Get instance screenshot (helps debug GUI issues)
aws ec2 get-console-screenshot --instance-id i-0abc123def456

使用 Terraform 配置 EC2 自动扩缩

resource "aws_launch_template" "web" {
  name_prefix   = "web-"
  image_id      = data.aws_ami.amazon_linux.id
  instance_type = "t3.medium"

  iam_instance_profile {
    name = aws_iam_instance_profile.web.name
  }

  metadata_options {
    http_tokens   = "required"
    http_endpoint = "enabled"
  }

  block_device_mappings {
    device_name = "/dev/xvda"
    ebs {
      volume_size = 30
      volume_type = "gp3"
      encrypted   = true
    }
  }

  user_data = base64encode(file("userdata.sh"))

  tag_specifications {
    resource_type = "instance"
    tags = {
      Name        = "web-server"
      Environment = "production"
    }
  }
}

resource "aws_autoscaling_group" "web" {
  name                = "web-asg"
  min_size            = 2
  max_size            = 10
  desired_capacity    = 4
  vpc_zone_identifier = [aws_subnet.private_a.id, aws_subnet.private_b.id]
  target_group_arns   = [aws_lb_target_group.web.arn]
  health_check_type   = "ELB"

  launch_template {
    id      = aws_launch_template.web.id
    version = "$Latest"
  }

  tag {
    key                 = "Name"
    value               = "web-asg"
    propagate_at_launch = true
  }
}

resource "aws_autoscaling_policy" "cpu" {
  name                   = "cpu-target-tracking"
  autoscaling_group_name = aws_autoscaling_group.web.name
  policy_type            = "TargetTrackingScaling"

  target_tracking_configuration {
    predefined_metric_specification {
      predefined_metric_type = "ASGAverageCPUUtilization"
    }
    target_value = 60.0
  }
}

故障排查

问题	原因	解决方法
实例卡在 pending 状态	容量不足	尝试其他可用区或实例类型
无法通过 SSH 连接实例	安全组或 NACL 阻止了 22 端口	检查 SG 入站规则和路由表
实例立即终止	EBS 卷限制或 AMI 问题	使用 describe-instances 检查 StateReason
IMDSv1 弃用警告	未设置元数据选项	在启动模板中设置 HttpTokens=required
用户数据未运行	脚本缺少 shebang 或未进行 Base64 编码	确认存在 #!/bin/bash 文件头；检查 /var/log/cloud-init-output.log
Spot 实例已终止	AWS 收回了容量	使用容量优化型分配策略并选择多种实例类型
ASG 未替换运行状况不佳的实例	运行状况检查宽限期太短	延长宽限期，使其覆盖应用启动时间
EBS 吞吐量成为瓶颈	gp2 卷太小，无法提供所需 IOPS	迁移到 gp3 并明确设置 IOPS/吞吐量

相关技能

• aws-vpc - VPC 网络、子网和安全组
• aws-iam - 实例配置文件和角色
• aws-cost-optimization - 合理调整资源规格和 Spot 策略
• terraform-aws - 使用基础设施即代码进行部署
• cloudformation - AWS 原生 IaC 模板