TOP 50 Interview Questions on AWS Cloud Computing Services -RDS

1. What is Amazon RDS?

Amazon Relational Database Service may be a managed service that creates it easy to line up, operate, and scale a Relational database within the cloud. It provides efficient cost and capacity resizable, while managing time consuming database administration tasks, freeing you up to specialise in your applications and business.

Amazon RDS gives you access to the capabilities of a well-known MySQL, MariaDB, Oracle, SQL Server, or PostgreSQL database. This means that the code, applications, and tools you already use today together with your existing databases should work seamlessly with Amazon RDS. Amazon RDS can automatically copy your database and keep your database software up so far with the newest version. You enjoy the pliability of having the ability to simply scale the compute resources or storage capacity related to your electronic database instance. As with all Amazon Web Services, there are not any up-front investments required, and you pay just for the resources you employ .

2. Which relational database engines does Amazon RDS support?

It supports Amazon Aurora, MySQL, MariaDB, Oracle, SQL Server, and PostgreSQL database engines.

3. How do I get started with Amazon RDS?

To check in for Amazon RDS, you want to have an Amazon Web Services account. After you’re signed up, please ask for the Amazon RDS documentation, which incorporates our Getting Started Guide.

Amazon RDS is part of the AWS Free Tier so that new AWS customers can get started with a managed database service in the cloud for free.

4. What is a database instance (DB instance)?

You can consider a DB instance as a database environment within the cloud with the compute and storage resources you specify. You may delete and create DB instances, define and refine infrastructure attributes of your control access, and DB instance, and security via the Amazon RDS APIs,  AWS Management Console,and AWS Command Line Interface. You can run one or more DB instances, and every DB instance can support one or more databases or database schemas, counting on engine type.

5. How do I create a DB instance?

DB instances are simple to make , using either the AWS Management Console, Amazon RDS APIs, or AWS instruction Interface. Using the AWS Management Console launch a DB instance, click “RDS,” then the Launch DB Instance button on the Instances tab. From there, you’ll specify the parameters for your DB instance including DB engine and version, license model, instance type, storage type and amount, and master user credentials.

You also have the power to vary your DB instance’s backup retention policy, preferred backup window, and care window. Using the CreateDBInstance API or create-db-instance command, Alternatively you’ll create your DB instance .

6. How do I access my running DB instance?

Once It is out, within the AWS Management Console you will retrieve its endpoint via the DB instance description, DescribeDBInstances API or describe-db-instances command. Using this endpoint you’ll construct the connection string required to attach directly together with your DB instance using your favorite database tool or programming language . In order to permit network requests to your running DB instance, you’ll have to authorize access. For an in depth explanation of the way to construct your connection string and obtain started, please ask our Getting Started Guide.

7. How many DB instances can I run with Amazon RDS?

By default, customers are allowed to possess up to a complete of 40 Amazon RDS DB instances. Of those 40, up to 10 are often Oracle or SQL Server DB instances under the “License Included” model. All 40 are often used for Amazon Aurora, MySQL, MariaDB, PostgreSQL and Oracle under the “BYOL” model. Note that RDS for SQL Server features a limit of up to 100 databases on one DB instance to find out more see the Amazon RDS SQL Server User Guide.

8. How many databases or schemas can I run within a DB instance?

RDS for Amazon Aurora: By software there is no limit imposed 

RDS for MySQL: No limit imposed by software

RDS for MariaDB: No limit imposed by software

RDS for Oracle: No limit on number of schemas per database imposed by software, 1 database per instance.

RDS for SQL Server: Amazon RDS SQL Server User Guide Up to 100 databases per instance see here.

RDS for PostgreSQL: No limit imposed by software

9. Which relational database engine versions does Amazon RDS support?

For the list of supported database engine versions, please ask the documentation for every engine:

• Amazon RDS for MySQL
• Amazon RDS for MariaDB
• Amazon RDS for PostgreSQL
• Amazon RDS for Oracle
• Amazon RDS for SQL Server
• Amazon Aurora

10. How does Amazon RDS distinguish between “major” and “minor” DB engine versions?

Refer to the FAQs page for every Amazon RDS database engine for specifics on version numbering.

11. Does Amazon RDS provide guidelines for support of new DB engine versions?

Over time, Amazon RDS adds support for brand spanking new major and minor database engine versions. The number of latest versions supported will vary, supporting the frequency and content of releases and patches from the engine’s vendor or development organization, and therefore the outcome of a thorough vetting of those releases and patches by our database engineering team. 

12. What does the AWS Free Tier for Amazon RDS offer?

The AWS Free Tier for Amazon RDS offer provides free use of Single-AZ Micro DB instances running MySQL, MariaDB, PostgreSQL, Oracle (“Bring-Your-Own-License (BYOL)” licensing model) and SQL Server Express Edition. 750 instance hours per month for the free usage tier. Customers also receive 20 GB of General Purpose database storage and 20 GB of backup storage for free of charge per month.

13. Can I run more than one DB instance under the AWS Free Usage Tier for Amazon RDS?

Yes. You can run more than one Single-AZ Micro DB instance simultaneously and be eligible for usage counted under the AWS Free Tier for Amazon RDS. If any use of 750 instance hours is exceeded, across all Amazon RDS Single-AZ Micro DB instances, across all eligible database engines and regions, are going to be billed at standard Amazon RDS prices.

14. What is a reserved instance (RI)?

Amazon RDS reserved instances offer you the choice to order a DB instance for a 1 or three year term and successively receive a big discount compared to the on-demand instance pricing for the DB instance. There are three RI payment options — No Upfront, Partial Upfront, All Upfront — which enable you to balance the amount you pay upfront with your effective hourly price.

15. How are reserved instances different from on-demand DB instances?

Functionally, They are precisely the same. The only difference is how your DB instance(s) are billed: With Reserved Instances, you buy a 1 or three year reservation and reciprocally receive a lower effective hourly usage rate for the duration of the term. Unless you buy reserved instances during a Region, all DB instances are going to be billed at on-demand hourly rates.

16. Can I move a reserved instance from one Region or Availability Zone to another?

Each reserved instance is related to a selected Region, which is fixed for the lifetime of the reservation and can’t be changed. Each reservation can, however, be utilized in any of the available AZs within the associated Region.

17. Can I cancel a reservation?

No, you cannot cancel your reserved DB instance and the one-time payment (if applicable) is not refundable. You will still buy every hour during your Reserved DB instance term no matter your usage.

18. What is the hardware configuration for Amazon RDS storage?

EBS volumes for database and log storage are used by Amazon RDS. Depending on the dimensions of storage requested, Amazon RDS automatically stripes across multiple EBS volumes to reinforce IOPS performance. For MySQL and Oracle, for an existing DB instance, you’ll observe some I/O capacity improvement if you proportion your storage. To your DB Instance using the AWS Management Console, the ModifyDBInstance API, or the modify-db-instance command  you can scale the storage capacity allocated.

19. What is Amazon RDS General Purpose (SSD) storage?

It is suitable for a broad range of database workloads that have moderate I/O requirements. With the baseline of three IOPS/GB and skill to burst up to three ,000 IOPS, this storage option provides predictable performance to satisfy the requirements of most applications.

20. What is Amazon RDS Provisioned IOPS (SSD) storage?

It is an SSD-backed storage option designed to deliver fast, predictable, and consistent I/O performance. With It, you specify an IOPS rate when creating a DB instance, and Amazon RDS provisions that IOPS rate for the lifetime of the DB instance. It is optimized for I/O-intensive, transactional (OLTP) database workloads.

21. What is Amazon RDS Magnetic storage?

Amazon RDS magnetic storage medium is beneficial for little database workloads where data is accessed less frequently. Magnetic storage isn’t recommended for production database instances.

22. How do I choose among the Amazon RDS storage types?

Choose the storage type most fitted to your workload.

High performance OLTP workloads: Amazon RDS Provisioned IOPS Storage

moderate I/O requirements with Database workloads: Amazon RDS General Purpose (SSD) Storage

23. Is there anything different about user management with Amazon RDS?

No, everything works the way you’re conversant in when employing an electronic database you manage yourself.

24. Can I use Amazon RDS with applications that require HIPAA compliance?

Yes, all RDS database engines are HIPAA-eligible, so you’ll use them to create HIPAA-compliant applications and store healthcare related information, including protected health information (PHI) under an executed Business Associate Agreement (BAA) with AWS. If you have already got an executed BAA, no action is important to start using these services within the account(s) covered by your BAA. If you do not have an executed BAA with AWS, or have any other questions about HIPAA-compliant applications on AWS, please contact your account manager.

25. How can I monitor the configuration of my Amazon RDS resources?

You can use AWS Config to continuously record configuration changes to Amazon RDS DB Instances, DB Subnet Groups, DB Snapshots, DB Security Groups, and Event Subscriptions and receive notification of changes through Amazon SNS. You can also create AWS Config Rules to gauge whether these RDS resources have the specified configurations.

26. What is an Availability Zone?

Availability Zones are distinct locations within a neighborhood that are engineered to be isolated from failures in other Availability Zones. Each Availability Zone runs on its own independent infrastructure, physically distinct, and highly reliable in engineering. Common failures like generators and cooling equipment are not shared across Availability Zones. Additionally, they’re physically separate, such even extremely uncommon disasters like fires, tornadoes or flooding would only affect one Availability Zone. Availability Zones within an equivalent Region enjoy low-latency network connectivity.

27. What happens when I convert my RDS instance from Single-AZ to Multi-AZ?

For the RDS for MySQL, MariaDB, PostgreSQL and Oracle database engines, when you elect to convert your RDS instance from Single-AZ to Multi-AZ, the following happens:

A snapshot of your primary instance is taken

A new standby instance is made during a different Availability Zone, from the snapshot

When an instance is converted from Single-AZ to Multi-AZ there should be no downtime incurred. However, you may see increased latency while the data on the standby is caught up to match the primary.

28. Do I need to enable automatic backups on my DB instance before I can create read replicas?

Yes. Enable automatic backups on your source DB Instance before adding read replicas, by setting the backup retention period to a worth aside from 0. Backups must remain enabled for read replicas to figure .

29. What is an RDS instance?

An instance is that the basic building block of an RDS. It is an isolated database environment running within the cloud. It manages the database instance by performing handling failover, backups, and maintaining the database software. Amazon RDS provides different instance types that are optimized to suit different electronic database use cases. Instance types comprise varying combinations of CPU, memory, and other resources to offer you flexibility in choosing the acceptable mixture of resources for your database.

30. List the database engines supported by Amazon RDS?

Below are the some of the database engines supported by the Amazon RDS,

• Amazon Aurora
• PostgreSQL
• MySQL
• MariaDB
• Oracle
• Microsoft SQL Server

31. Enlist some features of Amazon RDS?

Below are the some of the features of the Amazon RDS,

• 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 because it synchronously replicates the info to a standby instance during a different availability zone.
• It offers performance on par with the commercial database at 1/10th the value .
• It is highly secured as it lets you run database instances in Amazon Virtual Private Cloud.
• Using Amazon RDS is extremely cheap because the rates are very low and you enjoy the choice of On-Demand pricing.
• It also has support for Multi-availability zone deployment.

32. What is Amazon Aurora?

Amazon Aurora may be a sort of electronic database built for the cloud that’s 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 may be 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 patching, database setup, hardware provisioning, and backups are automated.

33. List some Amazon rds alternatives?

Some of the higher 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

34. What is the AWS RDS cluster?

An AWS Cluster consists of 1 or more RDS instances and a cluster volume to manage the info for the RDS instances. Aurora cluster is the popular one which creates two instances during a cluster by default. One instance is employed to write down while the opposite is employed for reading operation. But you can change this configuration as you wish.

35. Is Amazon RDS IaaS or PaaS?

Amazon RDS may be a PaaS because it only provides a platform or a group of tools to manage your database instances. AWS is Iaas, but the RDS provided by AWS is PaaS.

36. List Backup types supported by Amazon RDS?

There are two sorts of backups supported by Amazon RDS like automated backups and database snapshots.

Automated backup enables the point in time recovery of your DB instance automatically.

A DB snapshot may be a manual process to backup the DB instance. It can be done as frequently as you wish.

37. For what time period will the AWS Free Tier for Amazon RDS be available to me?

Receive 12 months of AWS Free Tier access for New AWS accounts .

38. How am I billed when my instance-hour usage exceeds the Free Tier benefit?

You are billed at standard Amazon RDS prices for instance hours beyond what the Free Tier provides.

39. Do reserved instances include a capacity reservation?

Amazon RDS reserved instances are purchased for a neighborhood instead of for a selected Availability Zone. As RIs aren’t specific to an Availability Zone, they’re not capacity reservations. This means that even if capacity is limited in one Availability Zone, reservations can still be purchased in the Region and the discount will apply to matching usage in any Availability Zone within that Region.

40. How many reserved instances can I purchase?

Up to 40 reserved DB instances you can purchase . If you wish to run more than 40 DB instances, complete the Amazon RDS DB Instance request form.

41. Are reserved instances available for Multi-AZ deployments?

Yes. When you purchase a reserved instance, you can select the Multi-AZ option in the DB instance configuration available for purchase. In addition, if you are using a DB engine and license model that supports reserved instance size-flexibility, a Multi-AZ reserved instance will cover usage for two Single-AZ DB instances.

42. Where are my automated backups and DB snapshots stored and how do I manage their retention?

Amazon RDS DB snapshots and automatic backups are stored in S3.

You can use the AWS Management Console, the ModifyDBInstance API, or the modify-db-instance command to manage the amount of your time your automated backups are retained by modifying the RetentionPeriod parameter. If you desire to show off automated backups altogether, you’ll do so by setting the retention period to 0 (not recommended). Via the “Snapshots” section of the Amazon RDS Console you can manage your user-created DB Snapshots. Alternatively, you’ll see an inventory of the user-created DB Snapshots for a given DB Instance using the DescribeDBSnapshots API or describe-db-snapshots command and delete snapshots with the DeleteDBSnapshot API or delete-db-snapshot command.

43. How is using Amazon RDS inside a VPC different from using it on the EC2-Classic platform (non-VPC)?

If your AWS account was created before 2013-12-04, you may be able to run Amazon RDS in an Amazon Elastic Compute Cloud (EC2)-Classic environment. The basic functionality of Amazon RDS is the same regardless of whether EC2-Classic or EC2-VPC is used. Amazon RDS manages automatic failure detection, software patching, backups, read replicas and recovery whether your DB Instances are deployed outside or inside a VPC. 

44. Can I move my existing DB instances outside VPC into my VPC?

If your DB instance isn’t during a VPC, you’ll use the AWS Management Console to simply move your DB instance into a VPC. You can also take a snapshot of your DB Instance outside VPC and restore it to VPC by specifying the DB Subnet Group you would like to use. Alternatively, you’ll perform a “Restore to Point in Time” operation also .

45. Can I move my existing DB instances from inside VPC to outside VPC?

Migration of DB Instances from inside to outside VPC isn’t supported. For security reasons, a DB Snapshot of a DB Instance inside VPC can’t be restored to outside VPC. 

46. What is an Amazon RDS master user account and how is it different from an AWS account?

To begin using Amazon RDS you’ll need an AWS developer account. If you do not have one prior to signing up for Amazon RDS, you will be prompted to create one when you begin the sign-up process. A master user account is different from an AWS developer account and used only within the context of Amazon RDS to regulate access to your DB Instance(s). The master user account may be a native database user account which you’ll use to attach to your DB Instance. You can specify the master user name and password you would like related to each DB Instance once you create the DB Instance. Once you’ve created your DB Instance, you’ll hook up with the database using the master user credentials. Subsequently, you may also want to create additional user accounts so that you can restrict who can access your DB Instance.

47. Can I encrypt data at rest on my Amazon RDS databases?

It supports encryption at rest for all database engines, using keys you manage using AWS Key Management Service. Data stored at rest within the underlying storage is encrypted, on a database instance running with Amazon RDS encryption, , as are its automated backups, read replicas, and snapshots. Encryption and decryption are handled transparently. For more information about the use of KMS with Amazon RDS, see the Amazon RDS User’s Guide.

You can also add encryption to a previously unencrypted DB instance or DB cluster by creating a DB snapshot then creating a replica of that snapshot and specifying a KMS encryption key. Amazon RDS for Oracle and SQL Server support those engines’ Transparent encoding (TDE) technologies. 

48. How do I choose the right configuration parameters for my DB Instance(s)?

By default, Amazon RDS chooses the optimal configuration parameters for your DB Instance taking under consideration the instance class and storage capacity. However, if you would like to vary them, you’ll do so using the AWS Management Console, the Amazon RDS APIs, or the AWS instruction Interface. Please note that changing configuration parameters from recommended values can have unintended effects, starting from degraded performance to system crashes, and will only be attempted by advanced users who wish to assume these risks.

49. Are there any performance implications of running my DB instance as a Multi-AZ deployment?

During a single Availability Zone observe elevated latencies relative to a typical DB instance deployment as a result of the synchronous data replication performed on your behalf.

50. How do I set up a Multi-AZ DB instance deployment?

When launching a DB Instance with the AWS Management Console simply click the “Yes” option for “Multi-AZ Deployment”. Alternatively, will use the Amazon RDS APIs, call the CreateDBInstance API and set the “Multi-AZ” parameter to the value “true”. To convert an existing standard (single AZ) DB instance to Multi-AZ, modify the DB instance within the AWS Management Console or use the ModifyDBInstance API and set the Multi-AZ parameter to true.