aws-rds

---

title: "Aws Rds" sidebar_label: "Aws Rds" description: "AWS RDS relational database service for managed databases. Use when provisioning databases, configuring backups, managing replicas, troubleshooting connectivity, or optimizing performance."

Aws Rds

AWS RDS relational database service for managed databases. Use when provisioning databases, configuring backups, managing replicas, troubleshooting connectivity, or optimizing performance.

Details

Property	Value
Skill Directory	.github/skills/aws-rds/
Phase	General
User Invocable	✅ Yes
Usage	/aws-rds Database engine, feature, or issue to look up (e.g. 'PostgreSQL Multi-AZ', 'read replica', 'IAM authentication', 'Performance Insights')

Documentation

AWS RDS

Amazon Relational Database Service (RDS) provides managed relational databases including MySQL, PostgreSQL, MariaDB, Oracle, SQL Server, and Aurora. RDS handles provisioning, patching, backups, and failover.

Table of Contents

• Core Concepts
• Common Patterns
• CLI Reference
• Best Practices
• Troubleshooting
• References

Core Concepts

DB Instance Classes

Category	Example	Use Case
Standard	db.m6g.large	General purpose
Memory Optimized	db.r6g.large	High memory workloads
Burstable	db.t3.medium	Variable workloads, dev/test

Storage Types

Type	IOPS	Use Case
gp3	3,000-16,000	Most workloads
io1/io2	Up to 256,000	High-performance OLTP
magnetic	N/A	Legacy, avoid

Multi-AZ Deployments

• Multi-AZ Instance: Synchronous standby in different AZ
• Multi-AZ Cluster: One writer, two reader instances (Aurora-like)

Read Replicas

Asynchronous copies for read scaling. Can be cross-region.

Common Patterns

Create a PostgreSQL Instance

AWS CLI:

# 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

boto3:

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
)

Create Read Replica

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

Take a Snapshot

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

Restore from Snapshot

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

Point-in-Time Recovery

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

Connect with IAM Authentication

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

CLI Reference

Instance Management

Command	Description
aws rds create-db-instance	Create instance
aws rds describe-db-instances	List instances
aws rds modify-db-instance	Modify settings
aws rds delete-db-instance	Delete instance
aws rds reboot-db-instance	Reboot instance
aws rds start-db-instance	Start stopped instance
aws rds stop-db-instance	Stop instance

Backups

Command	Description
aws rds create-db-snapshot	Manual snapshot
aws rds describe-db-snapshots	List snapshots
aws rds restore-db-instance-from-db-snapshot	Restore from snapshot
aws rds restore-db-instance-to-point-in-time	Point-in-time restore
aws rds copy-db-snapshot	Copy snapshot

Replicas

Command	Description
aws rds create-db-instance-read-replica	Create read replica
aws rds promote-read-replica	Promote to standalone

Best Practices

Security

• Never make publicly accessible — use VPC and security groups
• Enable encryption at rest (KMS) and in transit (SSL)
• Use IAM authentication for application access
• Store credentials in Secrets Manager with rotation
• Use parameter groups to enforce SSL

# 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"

Performance

• Right-size instances — monitor CPU, memory, IOPS
• Use gp3 for cost-effective performance
• Enable Performance Insights for query analysis
• Use read replicas for read scaling
• Optimize queries — check slow query log

High Availability

• Enable Multi-AZ for production
• Use Aurora for mission-critical workloads
• Configure appropriate backup retention
• Test failover periodically
• Monitor replication lag for replicas

Cost Optimization

• Use Reserved Instances for steady-state workloads
• Stop dev/test instances when not in use
• Delete old snapshots regularly
• Right-size instance classes

Troubleshooting

Cannot Connect

Causes:

1. Security group not allowing access
2. Instance not in VPC subnet
3. SSL required but not used
4. Wrong endpoint/port

Debug:

# 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

High CPU/Memory

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

Storage Full

# 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

Replication Lag

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

References

• RDS User Guide
• RDS API Reference
• RDS CLI Reference
• boto3 RDS