# Create DB subnet group
aws rds create-db-subnet-group \
  --db-subnet-group-name my-db-subnet-group \
  --db-subnet-group-description "Private subnets for RDS" \
  --subnet-ids subnet-12345678 subnet-87654321

# Create security group (allow PostgreSQL from app)
aws ec2 create-security-group \
  --group-name rds-postgres-sg \
  --description "RDS PostgreSQL access" \
  --vpc-id vpc-12345678

aws ec2 authorize-security-group-ingress \
  --group-id sg-rds12345 \
  --protocol tcp \
  --port 5432 \
  --source-group sg-app12345

# Create RDS instance
aws rds create-db-instance \
  --db-instance-identifier my-postgres \
  --db-instance-class db.t3.medium \
  --engine postgres \
  --engine-version 16.1 \
  --master-username admin \
  --master-user-password 'SecurePassword123!' \
  --allocated-storage 100 \
  --storage-type gp3 \
  --db-subnet-group-name my-db-subnet-group \
  --vpc-security-group-ids sg-rds12345 \
  --multi-az \
  --backup-retention-period 7 \
  --storage-encrypted \
  --no-publicly-accessible

import boto3

rds = boto3.client('rds')

response = rds.create_db_instance(
    DBInstanceIdentifier='my-postgres',
    DBInstanceClass='db.t3.medium',
    Engine='postgres',
    EngineVersion='16.1',
    MasterUsername='admin',
    MasterUserPassword='SecurePassword123!',
    AllocatedStorage=100,
    StorageType='gp3',
    DBSubnetGroupName='my-db-subnet-group',
    VpcSecurityGroupIds=['sg-rds12345'],
    MultiAZ=True,
    BackupRetentionPeriod=7,
    StorageEncrypted=True,
    PubliclyAccessible=False
)

aws rds create-db-instance-read-replica \
  --db-instance-identifier my-postgres-replica \
  --source-db-instance-identifier my-postgres \
  --db-instance-class db.t3.medium \
  --availability-zone us-east-1b

aws rds create-db-snapshot \
  --db-snapshot-identifier my-postgres-snapshot-2024-01-15 \
  --db-instance-identifier my-postgres

aws rds restore-db-instance-from-db-snapshot \
  --db-instance-identifier my-postgres-restored \
  --db-snapshot-identifier my-postgres-snapshot-2024-01-15 \
  --db-instance-class db.t3.medium \
  --db-subnet-group-name my-db-subnet-group \
  --vpc-security-group-ids sg-rds12345

aws rds restore-db-instance-to-point-in-time \
  --source-db-instance-identifier my-postgres \
  --target-db-instance-identifier my-postgres-pitr \
  --restore-time 2024-01-15T10:30:00Z \
  --db-instance-class db.t3.medium

# Change instance class (with downtime)
aws rds modify-db-instance \
  --db-instance-identifier my-postgres \
  --db-instance-class db.m6g.large \
  --apply-immediately

# Scale storage (no downtime)
aws rds modify-db-instance \
  --db-instance-identifier my-postgres \
  --allocated-storage 200 \
  --apply-immediately

import boto3
import psycopg2

rds = boto3.client('rds')

# Generate auth token
token = rds.generate_db_auth_token(
    DBHostname='my-postgres.abc123.us-east-1.rds.amazonaws.com',
    Port=5432,
    DBUsername='iam_user',
    Region='us-east-1'
)

# Connect
conn = psycopg2.connect(
    host='my-postgres.abc123.us-east-1.rds.amazonaws.com',
    port=5432,
    database='mydb',
    user='iam_user',
    password=token,
    sslmode='require'
)

# Enforce SSL in PostgreSQL
aws rds modify-db-parameter-group \
  --db-parameter-group-name my-pg-params \
  --parameters "ParameterName=rds.force_ssl,ParameterValue=1,ApplyMethod=pending-reboot"

# Check security group
aws ec2 describe-security-groups --group-ids sg-rds12345

# Check instance status
aws rds describe-db-instances \
  --db-instance-identifier my-postgres \
  --query "DBInstances[0].{Status:DBInstanceStatus,Endpoint:Endpoint}"

# Test connectivity from EC2
nc -zv my-postgres.abc123.us-east-1.rds.amazonaws.com 5432

# Enable Enhanced Monitoring
aws rds modify-db-instance \
  --db-instance-identifier my-postgres \
  --monitoring-interval 60 \
  --monitoring-role-arn arn:aws:iam::123456789012:role/rds-monitoring-role

# Enable Performance Insights
aws rds modify-db-instance \
  --db-instance-identifier my-postgres \
  --enable-performance-insights \
  --performance-insights-retention-period 7

# Enable storage autoscaling
aws rds modify-db-instance \
  --db-instance-identifier my-postgres \
  --max-allocated-storage 500

# Set CloudWatch alarm
aws cloudwatch put-metric-alarm \
  --alarm-name "RDS-Storage-Low" \
  --metric-name FreeStorageSpace \
  --namespace AWS/RDS \
  --dimensions Name=DBInstanceIdentifier,Value=my-postgres \
  --statistic Average \
  --period 300 \
  --threshold 10000000000 \
  --comparison-operator LessThanThreshold \
  --evaluation-periods 2 \
  --alarm-actions arn:aws:sns:us-east-1:123456789012:alerts

aws cloudwatch get-metric-statistics \
  --namespace AWS/RDS \
  --metric-name ReplicaLag \
  --dimensions Name=DBInstanceIdentifier,Value=my-postgres-replica \
  --start-time $(date -d '1 hour ago' -u +%Y-%m-%dT%H:%M:%SZ) \
  --end-time $(date -u +%Y-%m-%dT%H:%M:%SZ) \
  --period 60 \
  --statistics Average