Get prepared for your AWS RDS interview with these top questions and answers. Learn about the benefits of using AWS RDS, how to create and migrate databases, and how to scale and customize RDS instances. Also, find out how RDS handles maintenance and updates, and how it can be used with other AWS and non-AWS resources and many other.
AWS RDS Interview Questions
Q1. What is AWS RDS?
Q2. What is RDS DB instance?
Q3. Which database engines are supported with Amazon RDS?
Q4. What is the maximum number DB instances can user can run with Amazon RDS?
Q5. Explain some features in AWS RDS?
Q6. What are RDS Interfaces?
Q7. What is Amazon Aurora?
Q8. What is an AWS Cluster?
Q9. What is the work of Amazon RDS?
Q10. What is the purpose of standby RDS instance?
Q11. Enlist some features of Amazon RDS?
Q12. List some Amazon rds alternative?
Q13. Is Amazon RDS IaaS or PaaS?
Q14. What Backup types supported by Amazon RDS?
Q15. What benefits does the Amazon RDS AWS Free Tier provide?
Q16. What if I want to cover an existing database instance with a reserved instance?
Q17. What is the difference between an AWS account and an Amazon RDS primary user account?
Q18. On my Amazon RDS databases, can I encrypt data in transit?
Q19. What are some advantages of using AWS RDS?
Q20. How do you create a new RDS instance?
Q21. How do you migrate a database to AWS RDS?
Q22. Can you scale the compute and storage resources of an RDS instance independently?
Q23. Can you access the operating system of an RDS instance?
Q24. How does RDS handle database maintenance and updates?
Q25. Can you use RDS with other AWS services?
Q26. Can you use RDS with non-AWS resources?
Q27. What are the top Alternatives to Amazon RDS?
Q28. How to enable automated backups in RDS?
Q29. How does AWS RDS ensure high availability and reliability?
Q30. Which RDS database engines support multi-AZ deployment?
Q31. Which Amazon RDS database engine by default supports multi-AZ deployments?
Q32. What are the benefits and drawbacks of Amazon RDS?
Q33. Amazon RDS use cases
Q34. Explain RDS Read Replicas.
Q35. What is RDS Custom ?
Q36. What is RDS Proxy?
Q1. What is AWS RDS?
Amazon Relational Database Service (RDS) is a distributed relational database service provided by Amazon Web Services. It is a web service that runs “in the cloud” and is designed to facilitate the setup, operation, and scaling of a relational database to be used in applications.
Q2. What is RDS DB instance?
A DB instance is a standalone database environment in the AWS Cloud. Your DB instance may include numerous user-created databases. You can access your DB instance with the same tools and applications that you would use to access a standalone database instance.
Q3. Which database engines are supported with Amazon RDS?
Amazon RDS currently supports below databases:
- MySQL
- PostgreSQL
- MySQL
- MariaDB
- Oracle
- Microsoft SQL Server
Q4. What is the maximum number DB instances can user can run with Amazon RDS?
User are allowed to have up to 40 Amazon RDS DB instances by default. Under the “License Included” model, up to 10 from those 40 can be Oracle or SQL Server DB instances.
Q5. Explain some features in AWS RDS?
Amazon RDS Features:
- Lower administrative burden. Easy to use.
- Performance. General Purpose (SSD) Storage.
- Scalability. Push-button compute scaling.
- Availability and durability. Automated backups.
- Security. Encryption at rest and in transit.
- Manageability. Monitoring and metrics.
- Cost-effectiveness. Pay only for what you use.
Q6. What are RDS Interfaces?
Amazon provides an RDS interface to access the RDS service. To work with the RDS service like accessing the data, uploading the data, and running some other programs need an RDS interface.
There are three main interfaces provided such as GUI Console, Command Line Interface, and AWS API.
- A GUI Console is the simplest interface where users can easily work with the RDS Service.
- Command Line Interface gives you CLI access where you can execute DB commands to work with the service.
- An AWS API provides an Application Programming Interface to pass information between two systems.
Q7. What is Amazon Aurora?
Amazon Aurora is a type of relational database built for the cloud that is compatible with MySQL and PostgreSQL. It is five times faster than the MySQL database and three times faster than the PostgreSQL database. This hybrid database type is a perfect combination of the performance and availability of traditional databases with the simplicity and cost-effectiveness of the open-source database. This database is fully managed by the Amazon RDS so tasks like hardware provisioning, database setup, patching, and backups are automated.
Q8. What is an AWS Cluster?
An AWS Cluster consists of one or more RDS instances and a cluster volume to manage the data for the RDS instances. Aurora cluster is the popular one which creates two instances in a cluster by default. One instance is used to write while the other is used for reading operation. But you can change this configuration as you wish.
Q9. What is the work of Amazon RDS?
When a user wants to set up a relational database then Amazon RDS is used. It provisions the infrastructure capacity that a user requests to install the database software. Once the database is set up and functional RDS automates the tasks like patching up of the software, taking the backup of the data and management of synchronous data replication with automatic failover.
Q10. What is the purpose of standby RDS instance?
The main purpose of launching a standby RDS instance is to prevent the infrastructure failure (in case failure occurs) so it is stored in a different availability zone which is a totally different infrastructure physically and independently.
Q11. Enlist some features of Amazon RDS?
Some of the features of the Amazon RDS are,
- It is easy to administer the project from conception to deployment using the Amazon RDS as there is no need for infrastructure provisioning or installing and maintaining the database software.
- Amazon RDS is highly scalable. You can increase the compute and storage resource with only a few mouse clicks or an API call.
- It is a highly reliable infrastructure as it synchronously replicates the data to a standby instance in a different availability zone.
- It offers performance on par with the commercial database at 1/10th the cost.
- It is highly secured as it lets you run database instances in Amazon Virtual Private Cloud.
- Using Amazon RDS is very cheap as the rates are very low and you get the benefit from the option of On-Demand pricing.
- It also has support for Multi-availability zone deployment.
Q12. List some Amazon rds alternative?
Some of the better alternatives to the Amazon RDS are,
- Amazon Aurora
- Azure SQL Database
- Microsoft SQL Server
- Snowflake
- Oracle Database
- Google Cloud SQL
- MongoDB Atlas
- Oracle Exadata
- Oracle Database Cloud Service
Q13. Is Amazon RDS IaaS or PaaS?
Amazon RDS is a PaaS as it only provides a platform or a set of tools to manage your database instances. AWS is Iaas, but the RDS provided by the AWS is PaaS.
Q14. What are Backup types supported by Amazon RDS?
There are two types of backups supported by Amazon RDS, such as automated backups and database snapshots.
The automated backup enables point-in-time recovery of your DB instance automatically.
A DB snapshot is a manual process to backup the DB instance. It can be done as frequently as you wish.
Q15. What benefits does the Amazon RDS AWS Free Tier provide?
The Bring-Your-Own-License (BYOL) licensing model for Oracle, MySQL, MariaDB, PostgreSQL, and SQL Server Express Edition are supported under the AWS Free Tier for Amazon RDS service. There is a monthly limit of 750 instance hours for the free use tier. Customers also get 20 GB of free backup storage and 20 GB of general purpose (SSD) database storage each month.
Q16. What if I want to cover an existing database instance with a reserved instance?
Simply acquire a DB instance reservation in the same Region as the DB instance you are presently running and want to reserve, with the same DB instance class, DB engine, Multi-AZ option, and License Model. If the reservation purchase is successful, Amazon RDS will immediately charge your existing DB instance with the new hourly usage fee.
Q17. What is the difference between an AWS account and an Amazon RDS primary user account?
You must have a developer account with AWS in order to use Amazon RDS. You will be asked to create one when you start the Amazon RDS sign-up process if you don’t already have one. A primary user account is utilised exclusively in the context of Amazon RDS to manage access to your DB Instance and is distinct from an AWS developer account (s). Your DB Instance can be accessed via the principal user account, which is a native database user account.
Each DB Instance can have a primary user name and password specified when the DB Instance is created. Once you have created your DB Instance, you can connect to the database using the primary user credentials. Subsequently, you may also want to create additional user accounts so that you can restrict who can access your DB Instance.
Q18. On my Amazon RDS databases, can I encrypt data in transit?
For all database engines supported by Amazon RDS, encryption at rest is supported using keys managed by AWS Key Management Service (KMS). A database instance running with Amazon RDS encryption encrypts all automated backups, read replicas, snapshots, and data stored at rest in the underlying storage. The handling of encryption and decryption is transparent.
By producing a DB snapshot, a copy of that snapshot, and a KMS encryption key, you may also add encryption to a previously unencrypted DB instance or DB cluster. After that, you can use the encrypted snapshot to restore an encrypted database instance or database cluster. Amazon RDS for Oracle and SQL Server support those engines’ Transparent Data Encryption (TDE) technologies.
Q19. What are some advantages of using AWS RDS?
- Automated backups: RDS automatically takes backups of your database and stores them for a user-defined retention period.
- Scaling: RDS allows you to easily scale your database’s compute and storage resources up or down.
- Monitoring: RDS provides detailed monitoring and logging of database activity, enabling you to diagnose and troubleshoot performance issues.
- Security: RDS allows you to secure your database with encryption, network access controls, and identity and access management.
Q20. How do you create a new RDS instance?
To create a new RDS instance, you can use the AWS Management Console, the AWS RDS APIs, or the AWS Command Line Interface (CLI). Here are the high-level steps:
- Choose the database engine and version you want to use.
- Choose the instance class, which determines the compute and memory resources allocated to the instance.
- Configure the storage for the instance, including the size and type of the disk volume.
- Set the database name and credentials.
- Configure the network and security settings for the instance.
Q21. How do you migrate a database to AWS RDS?
There are several ways to migrate a database to AWS RDS, depending on the size and complexity of your database and your requirements for downtime. Some common options include:
- Dump and restore: This method involves creating a database dump on the source database, transferring the dump file to the RDS instance, and then restoring the dump file to create the database on RDS. This can be done using database utilities such as mysqldump (for MySQL) or pg_dump (for PostgreSQL).
- Replication: This method involves setting up replication between the source database and the RDS instance, so that changes made on the source database are automatically replicated to the RDS instance. This can be done using native database replication features or third-party tools such as AWS Database Migration Service.
- High-speed data transfer: This method involves using a specialized data transfer tool such as AWS DataSync to transfer large amounts of data between the source database and the RDS instance at high speed.
Q22. Can you scale the compute and storage resources of an RDS instance independently?
Yes, RDS allows you to scale the compute and storage resources of an instance independently, using the AWS Management Console, the RDS APIs, or the AWS CLI. For most database engines, you can scale the compute resources by modifying the instance class (e.g., from a t2.micro to a t2.large). You can also scale the storage resources by modifying the size and type of the disk volume attached to the instance.
Q23. Can you access the operating system of an RDS instance?
No, RDS instances are managed by AWS, and you do not have direct access to the operating system or the underlying hardware.
Q24. How does RDS handle database maintenance and updates?
AWS RDS handles database maintenance and updates automatically, without any downtime or disruption to your applications. This includes applying security patches, bug fixes, and version upgrades. RDS provides options to control the timing of these updates, such as the ability to specify a maintenance window and to apply updates in a rolling fashion across multiple instances.
Q25. Can you use RDS with other AWS services?
Yes, RDS can be used in conjunction with a number of other AWS services to build scalable and highly available applications. Some examples include:
Amazon Elastic Container Service (ECS) or Amazon Elastic Kubernetes Service (EKS) to run containerized applications that use an RDS database.
Amazon Elastic Cache to improve the performance of an RDS database by caching frequently accessed data in memory.
Amazon Virtual Private Cloud (VPC) to secure and isolate an RDS instance in your own private network.
AWS Lambda to run custom logic triggered by events on an RDS instance, such as data updates or failures.
Q26. Can you use RDS with non-AWS resources?
Yes, RDS can be used with non-AWS resources such as on-premises servers or other cloud infrastructure. You can use tools such as AWS Direct Connect or AWS VPN to establish a secure connection between your non-AWS resources and RDS. You can also use services such as AWS Database Migration Service or AWS DataSync to migrate data to or from RDS.
Q27. What are the top Alternatives to Amazon RDS?
Below are the most popular alternatives and competitors to Amazon RDS.
- Amazon Redshift
- Apache Aurora
- MySQL, Oracle
- Heroku Postgres
Q28. How to enable automated backups in RDS?
You can enable automated backups in RDS in below ways:
1) Using RDS API:
You can use the RDS API ModifyDBInstance operation to enable automated backups in RDS with the following required parameters:
DBInstanceIdentifier
BackupRetentionPeriod
2) From AWS Console
Sign in to the AWS and go to Amazon RDS console at https://console.aws.amazon.com/rds/.
Navigation pane -> Select databases -> Select DB instance that you want to modify.
Select Backup retention period -> Provide a nonzero positive value, like 5 days.
Choose Continue -> Choose Apply immediately.
Q29. How AWS RDS ensure high availability and reliability?
AWS RDS allows multi-AZ deployment to ensure high availability and reliability.
With the use of multi-AZ deployment feature, AWS automatically provisions and maintains a synchronous standby replica in a different Availability Zone.
AWS synchronously replicates the data from the primary to the secondary database instance.
Failover Support: In case if the primary database instance fails or gets shut down in any way, AWS will automatically fail over to another secondary database instance.
Q30. Which RDS database engines support multi-AZ deployment?
AWS RDS allows multi-AZ deployment to ensure high availability and reliability. Multi-AZ deployments support can be used for below RDS database engine:
- MariaDB
- MySQL
- Oracle
- PostgreSQL
Q31. Which Amazon RDS database engine by default supports multi-AZ deployments?
Amazon RDS offers Multi-AZ deployments with Always On AGs for the listed SQL Server versions and editions:
- SQL Server 2019
- Standard and Enterprise Editions.
- SQL Server 2017
- Enterprise Edition 14.00. 3049.1 or higher.
Q32. What are the benefits and drawbacks of Amazon RDS?
There are several pros and cons to using Amazon RDS.
- Easy to administer: Amazon RDS makes it easy to go from project conception to deployment. Use the Amazon RDS Management Console, the AWS RDS Command-Line Interface, or simple API calls to access the capabilities of a production-ready relational database in minutes. No need for infrastructure provisioning and no need for installing and maintaining database software.
- Highly scalable: You can scale your database’s compute and storage resources with only a few mouse clicks or an API call, often with no downtime. Many Amazon RDS engine types allow you to launch one or more Read Replicas to offload read traffic from your primary database instance.
- Available and durable: Amazon RDS runs on the same highly reliable infrastructure used by other Amazon Web Services. When you provision a Multi-AZ DB Instance, Amazon RDS synchronously replicates the data to a standby instance in a different Availability Zone (AZ). Amazon RDS has many other features that enhance reliability for critical production databases, including automated backups, database snapshots, and automatic host replacement.
- Fast: Amazon RDS supports the most demanding database applications. You can choose between two SSD-backed storage options: one optimized for high-performance OLTP applications and the other for cost-effective general-purpose use. In addition, Amazon Aurora provides performance on par with commercial databases at 1/10th the cost.
- Secure: Amazon RDS makes it easy to control network access to your database. Amazon RDS also lets you run your database instances in Amazon Virtual Private Cloud (Amazon VPC), enabling you to isolate your database instances and connect to your existing IT infrastructure through an industry-standard encrypted IPsec VPN. Many Amazon RDS engine types offer encryption at rest and encryption in transit.
- Inexpensive: You pay very low rates and only for the resources you consume. In addition, you benefit from the option of On-Demand pricing with no up-front or long-term commitments or even lower hourly rates via our Reserved Instance pricing.
- Ease of use. Admins don’t need to learn specific database management tools, and they also can manage multiple database instances using the management console. RDS is compatible with database engines that users may already be familiar with, such as MySQL and Oracle, and it automates manual backup and recovery processes.
- Cost-effectiveness. According to AWS, customers only pay for what they use. Also, the time spent maintaining instances is reduced because maintenance tasks, such as backups and patching are automated.
Drawbacks
Some downsides of using Amazon RDS include the following:
- Lack of root access. Because it is a managed service, users do not have root access to the server running RDS. RDS restricts access for certain procedures to those with advanced privileges.
- Downtime. Systems must go offline for some patching and scaling procedures, and the timing of these processes varies. With scaling, compute resources need a few minutes of downtime on average.
Q33. Amazon RDS use cases
Amazon RDS’ scalability, security and availability make it useful for a variety of applications. Some possible uses include the following:
- Online retailing.These applications manage complex databases that track inventories, transactions and pricing.
- Mobile and online gaming. RDS supports developers that need to update these applications and users who need high availability continuously.
- Travel applications. Applications like Airbnb take advantage of RDS’ ability to simplify time-consuming database administration tasks and automate database replication. Mobile apps like Airbnb also take advantage of RDS’ scalable storage capability.
- Streaming applications. Applications like Netflix take advantage of RDS’s storage scalability and the availability of Amazon RDS, which allows them to handle high demand daily.
- Finance applications. Like other mobile applications, these applications can use RDS to simplify administrative database tasks and save time and money.
Q34. Explain RDS Read Replicas.
RDS can have upto 5 read replicas, multi AZ, within AZ or cross region, Replication is ASYNC so events are eventually consistent. Read replicas within same region = free, no charge, Read replicas cross region= Fees $
Q35. What is RDS Custom ?
RDS CUSTOM lets you managed Oracle & Microsoft SQL servers database with OS and database customizations. Can configure settings, install patches and access underlying EC2 instances. Need to deactivate automation mode to perform customizations.
Q36. What is RDS Proxy?
RDS Proxy is fully managed database proxy for RDS. Allows apps to pool and share database connections with database. Improves database efficiency by reducing stress on database. Serverless, autoscaling, high availability. Reduces RDS & Aurora failover time by 66%. Supports RDS – Postgres, MySQL & MariaDB. Supports Aurora – Postgres and MySQL. RDS proxy is never publicaly accessible, must be accessed from VPC.
Final Words
Learning all technicalities related to RDS is very important while going for AWS RDS Interview. We try to keep all AWS RDS Interview Questions and Answers.
Good Luck, Happy Learning 🙂