AWS RDS 설정 가이드 — 인스턴스·파라미터·백업·스냅샷

# PostgreSQL 인스턴스 생성
aws rds create-db-instance \
  --db-instance-identifier my-postgres \
  --db-instance-class db.t3.medium \
  --engine postgres \
  --engine-version 16.2 \
  --master-username admin \
  --master-user-password "SecurePass123!" \
  --allocated-storage 100 \
  --storage-type gp3 \
  --storage-encrypted \
  --vpc-security-group-ids sg-xxxxxxxx \
  --db-subnet-group-name my-subnet-group \
  --backup-retention-period 7 \
  --no-publicly-accessible \
  --multi-az \
  --deletion-protection

# 생성 상태 확인
aws rds describe-db-instances \
  --db-instance-identifier my-postgres \
  --query 'DBInstances[0].DBInstanceStatus'

# RDS 보안 그룹 — 앱 서버 SG에서만 5432 허용
aws ec2 authorize-security-group-ingress \
  --group-id sg-rds-xxxxxx \
  --protocol tcp \
  --port 5432 \
  --source-group sg-app-xxxxxx

# 퍼블릭 접근 확인
aws rds describe-db-instances \
  --query 'DBInstances[0].PubliclyAccessible'

# 파라미터 그룹 생성
aws rds create-db-parameter-group \
  --db-parameter-group-name my-postgres16 \
  --db-parameter-group-family postgres16 \
  --description "Custom PostgreSQL 16 params"

# 파라미터 수정
aws rds modify-db-parameter-group \
  --db-parameter-group-name my-postgres16 \
  --parameters \
    "ParameterName=shared_buffers,ParameterValue={DBInstanceClassMemory/4},ApplyMethod=pending-reboot" \
    "ParameterName=log_min_duration_statement,ParameterValue=1000,ApplyMethod=immediate" \
    "ParameterName=max_connections,ParameterValue=200,ApplyMethod=pending-reboot"

# 인스턴스에 파라미터 그룹 적용
aws rds modify-db-instance \
  --db-instance-identifier my-postgres \
  --db-parameter-group-name my-postgres16 \
  --apply-immediately

# 자동 백업 설정 확인
aws rds describe-db-instances \
  --db-instance-identifier my-postgres \
  --query 'DBInstances[0].{Backup:BackupRetentionPeriod,Window:PreferredBackupWindow}'

# 수동 스냅샷 생성
aws rds create-db-snapshot \
  --db-instance-identifier my-postgres \
  --db-snapshot-identifier my-postgres-snap-$(date +%Y%m%d)

# 스냅샷 목록
aws rds describe-db-snapshots \
  --db-instance-identifier my-postgres \
  --query 'DBSnapshots[*].[DBSnapshotIdentifier,SnapshotCreateTime,Status]' \
  --output table

# 스냅샷에서 복원
aws rds restore-db-instance-from-db-snapshot \
  --db-instance-identifier my-postgres-restored \
  --db-snapshot-identifier my-postgres-snap-20250527

# 읽기 복제본 생성
aws rds create-db-instance-read-replica \
  --db-instance-identifier my-postgres-reader \
  --source-db-instance-identifier my-postgres \
  --db-instance-class db.t3.small

# 복제본 엔드포인트 확인
aws rds describe-db-instances \
  --db-instance-identifier my-postgres-reader \
  --query 'DBInstances[0].Endpoint'

# 엔드포인트 조회
aws rds describe-db-instances \
  --db-instance-identifier my-postgres \
  --query 'DBInstances[0].Endpoint.Address' \
  --output text

# EC2에서 연결 테스트
psql -h my-postgres.xxxxxxxx.ap-northeast-2.rds.amazonaws.com \
  -U admin -d postgres -p 5432