Chapter 4 - DATABASES: Amazon RDS, Amazon Aurora, Amazon DynamoDB, Elasticache, Amazon DocumentDB Flashcards

Question

You have used Multi-AZ deployment for Amazon RDS instances for your web application to achieve enhanced database availability and durability. You know that Amazon RDS maintains an up-to-date standby instance which is synchronously updated. What happens during Multi-AZ failover? Choose 2. 1. Failover is automatically handled by Amazon RDS so that you can resume database operations as quickly as possible without administrative intervention. 2. Amazon RDS simply flips the canonical name record (CNAME) for your DB instance to point at the standby, which is in turn promoted to become the new primary. 3. Amazon RDS simply flips the canonical name record (CNAME) for your DB instance to point at alternate ‘failover’ record which needs to be created by you in the Route 53 hosted zone . 4. Amazon RDS simply flips the A Record type for your DB instance to point at the standby, which is in turn promoted to become the new primary. 5. Amazon RDS simply flips the A Record type for your DB instance to point at alternate ‘failover’ record which needs to be created by you in the Route 53 hosted zone.

Answer 1

1. **Failover is automatically handled by Amazon RDS so that you can resume database operations as quickly as possible without administrative intervention.** 2. **Amazon RDS simply flips the canonical name record (CNAME) for your DB instance to point at the standby, which is in turn promoted to become the new primary.** 3. Amazon RDS simply flips the canonical name record (CNAME) for your DB instance to point at alternate ‘failover’ record which needs to be created by you in the Route 53 hosted zone . 4. Amazon RDS simply flips the A Record type for your DB instance to point at the standby, which is in turn promoted to become the new primary. 5. Amazon RDS simply flips the A Record type for your DB instance to point at alternate ‘failover’ record which needs to be created by you in the Route 53 hosted zone.

Answer 2

1. Amazon RDS creates automated backups of your DB instance during the backup window of your DB instance. 2. Amazon RDS saves the automated backups of your DB instance according to the backup retention period that you specify. 3. You can recover your database to any point in time during the backup retention period. 4. **All of the above**

Answer 3

1. RDS will not take automated backups. 2. **RDS assigns a default 30-minute backup window.** 3. RDS will not allow to take manual backups. 4. RDS will not create the DB instance.

Answer 4

1. **The first snapshot of a DB instance contains the data for the full DB instance.** 2. **Subsequent snapshots of the same DB instance are incremental, which means that only the data that has changed after your most recent snapshot is saved.** 3. Subsequent snapshots of the same DB instance also contains the data of the full DB instance. 4. **You can copy both automatic and manual DB snapshots, and share manual DB snapshots.**

Answer 5

1. If you delete a RDS DB Instance there is no option to retain the automated backups. 2. You have to manually create copies of automated backups. 3. You can take snapshot of DB Instance before deleting it. 4. **Choose Retain automated backups when you delete a DB instance.**

Answer 6

1. A DB option group acts as a container for engine configuration values that are applied to one or more DB instances. 2. A DB parameter group acts as a container for engine feature which is empty by default. 3. **A DB parameter group acts as a container for engine configuration values that are applied to one or more DB instances.** 4. **A DB option group acts as a container for engine feature which is empty.**

Answer 7

1. The time it takes after a disruption to restore a database to its service level, as defined by the operational level agreement (OLA). 2. The acceptable amount of performance loss measured in time. 3. **The time it takes after a disruption to restore a business process to its service level, as defined by the operational level agreement (OLA).** 4. The acceptable amount of data loss measured in time.

Answer 8

1. The time it takes after a disruption to restore a database to its service level, as defined by the operational level agreement (OLA). 2. The acceptable amount of performance loss measured in time. 3. The time it takes after a disruption to restore a business process to its service level, as defined by the operational level agreement (OLA). 4. **The acceptable amount of data loss measured in time.**

Answer 9

1. **High-performance OLTP workloads: Amazon RDS Provisioned IOPS (SSD) Storage** 2. **Database workloads with moderate I/O requirements: Amazon RDS General Purpose (SSD) Storage** 3. High-performance OLTP workloads: Amazon RDS General Purpose (SSD) Storage 4. Database workloads with moderate I/O requirements: Amazon RDS Provisioned IOPS (SSD) Storage

Answer 10

1. EBS 2. DynamoDB 3. **S3** 4. DocumentDB

Answer 11

1. S3 2. **EBS** 3. EFS 4. Redshift

Answer 12

1. **8 PM** 2. 4 AM 3. 4 PM 4. 8AM

Answer 13

1. 11 PM 2. **11 AM** 3. 1 PM 4. 1 AM

Answer 14

1. **Elastic Block Store (Amazon EBS) volumes** 2. Amazon S3 3. Amazon Aurora 4. MySQL, MariaDB, PostgreSQL, Oracle, and Microsoft SQL Server

Answer 15

1. Throughput Optimized 2. **General Purpose SSD** 3. **Provisioned IOPS** 4. **Magnetic**

Answer 16

1. Throughput Optimized 2. General Purpose SSD 3. **Provisioned IOPS** 4. Magnetic

Answer 17

1. **Delivers predictable performance, and consistently low latency.** 2. **Optimized for online transaction processing (OLTP) workloads that have consistent performance requirements.** 3. **When you create a DB instance, you specify an IOPS rate and the size of the volume.** 4. Designed for throughput-intensive workloads.

Answer 18

1. System activities: Multi-AZ standby creation, Read replica creation, changing storage types 2. Database or application design resulting in concurrency issues, locking, or other forms of database contention. 3. Instance type not with enough bandwidth to support your storage type. 4. **All of the above**

Answer 19

1. MySQL, MariaDB, PostgreSQL, Oracle, Microsoft SQL Server 2. **MySQL, MariaDB, PostgreSQL, Oracle, Amazon Aurora** 3. MySQL, PostgreSQL, Oracle, Microsoft SQL Server, Amazon Aurora 4. MySQL, MariaDB, Oracle, Microsoft SQL Server, Amazon Aurora

Answer 20

1. **Scaling beyond the compute or I/O capacity of a single DB instance for read-heavy database workloads.** 2. **Serving read traffic while the source DB instance is unavailable.** 3. Improving performance of a single DB instance for update heavy database workloads. 4. Serving update traffic while the source DB instance is unavailable.

Answer 21

1. **Business reporting or data warehousing scenarios where you might want business reporting queries to run against a Read Replica, rather than your primary, production DB instance.** 2. For storing user session data. 3. **Implementing disaster recovery.** 4. All of the above.

Answer 22

1. **Amazon RDS takes a snapshot of the source instance and creates a read-only instance from the snapshot.** 2. Amazon RDS uses the synchronous replication method for the DB engine to update the Read Replica whenever there is a change to the source DB instance. 3. You have to create manually a separate copy of the main primary DB instance and mark it as Read Replica. 4. **Amazon RDS uses the asynchronous replication method for the DB engine to update the Read Replica whenever there is a change to the source DB instance.**

Answer 23

1. The Read Replica operates as a DB instance that allows update-only connections. 2. Amazon RDS replicates only those databases chosen by the user in the source DB instance. 3. **The Read Replica operates as a DB instance that allows read-only connections.** 4. **Amazon RDS replicates all databases in the source DB instance.**

Answer 24

1. Amazon RDS doesn't support circular replication. 2. **Amazon RDS supports circular replication.** 3. Read Replica can resides in a different AWS Region than its source DB instance. 4. **Read Replica cannot resides in a different AWS Region than its source DB instance.**

Answer 25

1. Amazon RDS for MySQL 2. Amazon RDS for PostgreSQL 3. **Amazon RDS Aurora** 4. Amazon RDS for Oracle

Answer 26

1. **Two types of DB instances make up an Aurora DB cluster: Primary DB instance & Aurora Replica** 2. For primary DB instance failover you need to have a separate instance apart from Replica. 3. **Primary DB instance supports read and write operations, and performs all of the data modifications to the cluster volume. Each Aurora DB cluster has one primary DB instance.** 4. **Aurora Replica connects to the same storage volume as the primary DB instance and supports only read operations. Each Aurora DB cluster can have up to 15 Aurora Replicas in addition to the primary DB instance.**

Answer 27

1. **Cluster endpoint** 2. **Reader endpoint** 3. Write endpoint 4. **Custom endpoint**

Answer 28

1. **Aurora cluster volumes automatically grow as the amount of data in your database increases.** 2. **An Aurora cluster volume can grow to a maximum size of 64 tebibytes (TiB).** 3. An Aurora cluster volume can grow to a maximum size of 64 terabytes (TB). 4. **Aurora data is stored in the cluster volume consisting of copies of the data across multiple Availability Zones in a single AWS Region.**

Answer 29

1. Instead of MySQL use Oracle or SQL Server. 2. Instead of MySQL use DynamoDB. 3. Use Multi-AZ deployment option to increase read and write performance. 4. **Use Read Replicas and redirect read queries to those replicas.**

Answer 30

1. **5** 2. 10 3. 15 4. 20

Answer 31

1. 5 2. 10 3. **15** 4. 20

Answer 32

1. **Improving performance** 2. Improving Security 3. Improving Availability 4. Improving Durability

Answer 33

1. You can make a snapshot from a read replica and promote if the source DB instance fails. 2. **You can promote a read replica if the source DB instance fails.** 3. **You can set up a read replica with its own standby instance in different AZ.** 4. Read replica automatically enables Multi-AZ deployment.

Answer 34

1. **Configure source database as Multi-AZ for high availability** 2. **Create Read Replica for read scalability** 3. Create Read Replica for high availability 4. Configure Multi-AZ for read scalability

Answer 35

1. Read Replicas are enabled as DR target by default. 2. **Set the read replica as Multi-AZ, allowing you to use the read replica as a DR target.** 3. Set the read replica as Single-AZ, allowing you to use the read replica as a DR target. 4. None of the above.

Answer 36

1. In Read Replicas only database engine on primary instance is active while in Multi-AZ all replicas are accessible and can be used for read scaling. 2. **Multi-AZ Deployments have synchronous replication and is highly durable while Read Replicas have Asynchronous replication and is highly scalable.** 3. **In Multi-AZ only database engine on primary instance is active while in Read Replicas all read replicas are accessible and can be used for read scaling.** 4. Read Replicas have synchronous replication and is highly durable while Multi-AZ have Asynchronous replication and is highly scalable.

Answer 37

1. **In Multi-AZ Automated backups are taken from standby while in Read Replicas no backups configured by default.** 2. In Read Replicas Automated backups are taken from standby while In Multi-AZ no backups configured by default. 3. Read Replicas always span two Availability Zones within a single Region while Multi-AZ can be within an Availability Zone, Cross-AZ, or Cross-Region. 4. **Multi-AZ always span two Availability Zones within a single Region while Read Replicas can be within an Availability Zone, Cross-AZ, or Cross-Region.**

Answer 38

1. **In Multi-AZ automatic failover to standby when a problem is detected.** 2. In Read Replica automatic failover to standby when a problem is detected. 3. In Multi-AZ, instance can be manually promoted to a standalone database instance. 4. **In Read Replica, instance can be manually promoted to a standalone database instance.**

Answer 39

1. **I/O may be briefly suspended while the backup process initializes (typically under a few seconds) and you may experience a brief period of elevated latency.** 2. No effect on I/O 3. There is no I/O suspension, since the backup is taken from the standby. 4. None of the above

Answer 40

1. Ensure that underlying RDS MySQL instance is Multi-AZ enabled. 2. **Create a read replica for underlying RDS MySQL**. 3. Change the RDS instance from MySQL to PostgreSQL. 4. Analyze and improve the performance of read queries.

Answer 41

1. No need to do anything, automated backup are retained even after deleting the DB instance. 2. **Create a final user created DB snapshot upon deletion.** 3. No need to do anything, RDS automatically creates a final DB snapshot when deleting the DB instance is initiated. 4. There is no way to recreate a RDS instance after it is deleted.

Answer 42

1. **Sticky Sessions with Local Session Caching including a client-side cookies or via configurable duration parameters that can be set at the load balancer which routes requests to the web servers.** 2. Distributed Session Management using ElastiCache, Redshift, RDS 3. **Distributed Session Management using ElastiCache, DynamoDB, RDS** 4. Distributed Session Management using ElastiCache, S3, RDS

Answer 43

1. **A collection of subnets that you may want to designate for your RDS DB Instances in a VPC.** 2. **When creating a DB Instance in VPC, you will need to select a DB Subnet Group.** 3. When creating a DB Instance in VPC, you don’t need to select a DB Subnet Group. 4. **Each DB Subnet Group should have at least one subnet for every Availability Zone in a given Region.**

Answer 44

1. You cannot create a read replica with a Multi-AZ DB instance deployment as its source. 2. **You can create a read replica with a Multi-AZ DB instance deployment as its source.** 3. **You can configure read replicas themselves as Multi-AZ** 4. You cannot configure read replicas themselves as Multi-AZ

Answer 45

1. You cannot create a read replica with a Multi-AZ DB instance deployment as its source. 2. **Any associated and available read replicas will automatically resume replication once failover has completed.** 3. You have to manually map the read replicas to newly promoted primary to resume replication. 4. You have to delete the old read replicas and new read replicas will be created by RDS after a new primary is promoted.

Answer 46

1. **A database parameter group (DB Parameter Group) acts as a “container” for engine configuration values that can be applied to one or more DB Instances.** 2. You cannot create a new DB parameter group with custom configuration engine values. 3. **RDS provides a default parameter group optimized for DB instance.** 4. It is mandatory to specify a DB parameter group when creating a DB instance.

Answer 47

1. **IOPS** 2. **Latency** 3. Network Bandwidth 4. **Throughput** 5. **Queue Depth**

Answer 48

1. Multi-AZ standby creation. 2. Read replica creation. 3. Changing storage types. 4. **EBS-optimized instances and instances with 10-gigabit network connectivity.**

Answer 49

1. **Download Amazon RDS root CA certificate to your web server and use Secure Socket Layer (SSL) or Transport Layer Security (TLS) from your application to encrypt a connection to DB instance.** 2. All the connection between EC2 instances and RDS databases are by default encrypted. 3. Force all connections to your DB instance to use SSL by setting the rds.force\_ssl parameter to 1 (on) 4. Add the SSL option to the option group associated with the DB instance.

Answer 50

1. Step1: You create a new DB instance with encryption enabled 2. Step 2: Copy data from the old DB instance to new encrypted DB instance 3. **Step1: You can create a snapshot of your DB instance, and then create an encrypted copy of that snapshot.** 4. **Step2: You can then restore a DB instance from the encrypted snapshot, and thus you have an encrypted copy of your original DB instance.**

Answer 51

1. AES-128 2. **AES-256** 3. DES-256 4. DES-128

Answer 52

1. **When you create an encrypted DB instance, you can also supply the AWS KMS key identifier for your encryption key.** 2. **If you don't specify an AWS KMS key identifier, then Amazon RDS uses your default encryption key for your new DB instance.** 3. Once you have created an encrypted DB instance, you can change the type of encryption key used by that DB instance. 4. **Once you have created an encrypted DB instance, you can't change the type of encryption key used by that DB instance.**

Answer 53

1. **DB security group** 2. **VPC security group** 3. **EC2 security group** 4. RDS Security group

Answer 54

1. **DB SG controls access to DB instances outside a VPC while VPC SG controls access to DB instances in VPC.** 2. In both DB SG and VPC SG when you add a rule to a group, you need to specify the protocol as TCP. In addition, specify the same port number that you used to create the DB instances (or options) that you plan to add as members to the group. 3. **In DB SG when you add a rule to a group, you don't need to specify port number or protocol. In VPC SG when you add a rule to a group, you need to specify the protocol as TCP. In addition, specify the same port number that you used to create the DB instances (or options) that you plan to add as members to the group.** 4. **DB SG allow access from EC2 security groups in your AWS account or other accounts. VPC SG allow access from other VPC security groups in your VPC only.**

Answer 55

1. Once you disable and you cannot re-enable automated backups 2. **It disables point-in-time recovery** 3. **Deletes all existing automated backups for the instance** 4. Existing automated backups for the instance are retained

Answer 56

1. You have to manually delete new scripts to come back to original state. 2. **RDS MySQL has the feature ‘Restore to point in time’ to restore a DB instance to a specific point in time.** 3. To manage risk first do the patch release in a DB copy without impacting original DB. 4. Enable Read Replica before making changes, to roll back delete the main DB.

Answer 57

1. No configuration required as Amazon RDS always encrypts the data at rest. 2. You can encrypt data in RDS DB instance but cannot encrypt snapshots. 3. **Enabling the encryption option for your Amazon RDS DB instances while creation.** 4. **While database creation supply the AWS KMS key identifier for your encryption key otherwise Amazon RDS uses your default encryption key for your new DB instance.**

Answer 58

1. **Enable RDS Enhanced Monitoring** 2. Use Amazon CloudWatch to monitor 3. Create custom program which collect data for any metric. 4. Use Amazon Cloudtrail logs to extract data for any metric.

Answer 59

1. Reserved Instance prices cover instance costs only. Storage and I/O are still billed separately. 2. **The RI discounted rate will apply to usage of Single-AZ configurations only for the same database engine and instance family. It will not be applicable for Multi-AZ configuration.** 3. Reserved Instances are available in all the AWS regions and for all supported DB Engines. 4. Reserved Instances for the MySQL, MariaDB, PostgreSQL, and Amazon Aurora database engines as well as the “Bring your own license” (BYOL) edition of the Oracle database engine offer instance size flexibility.

Answer 60

1. Data transferred between Amazon RDS and Amazon EC2 Instances in the same Availability Zone 2. Data transferred between Availability Zones for replication of Multi-AZ deployments 3. **Data transferred to copy the DB snapshot data across regions.** 4. **Data transferred between an Amazon EC2 instance and Amazon RDS DB Instance in different Availability Zones of the same Region**

Answer 61

1. **Lambda** 2. **Aurora Serverless** 3. S3 4. RDS MySQL

Answer 62

1. Predictable workloads 2. **Infrequently used applications** 3. **New applications where you are unsure of capacity requirements.** 4. **Variable and unpredictable workloads**

Answer 63

1. **Take a DB snapshot of the DB instance after the survey is completed, delete the DB instance, and then restore the DB instance along with web application on EC2 when you need to conduct the survey again**. 2. AWS will not charge for EC2 and DB instance between the quarters when application is not being used. 3. Buy reserve capacity for EC2 and DB instance. 4. After the quarterly survey, when the application is not being used till next survey, change the instance class and storage of both EC2 and DB to lowest possible

Answer 64

1. Magnetic Storage 2. Provisioned IOPS Storage 3. **General Purpose SSD Storage** 4. Throughput Optimized Storage

Answer 65

1. Magnetic Storage 2. Provisioned IOPS Storage 3. Throughput Optimized Storage 4. **General Purpose SSD Storage**

Answer 66

1. Reserved instances are not available for RDS Multi-AZ 2. Reserved instances are not available for RDS Read Replicas 3. **Reserved instances are available for RDS Multi-AZ** 4. **Reserved instances are available for RDS Read Replicas**

Answer 67

1. You have to manually delete new scripts to come back to original state. 2. **RDS Aurora MySQL has the feature ‘Restore to point in time’ to restore a DB cluster to a specific point in time.** 3. To manage risk first do the patch release in a DB copy without impacting original DB. 4. **RDS Aurora MySQL has the feature to backtrack a DB Cluster to specific point in time, without restoring data from backup.**

Answer 68

1. **Amazon RDS Enhanced Monitoring** 2. **Amazon CloudWatch** 3. **Amazon RDS Events and Database log files** 4. Amazon Flow logs

Answer 69

1. **Monitors your Amazon RDS DB instance load so that you can analyze and troubleshoot your database performance.** 2. **The central metric for Performance Insights is DB Load, which represents the average number of active sessions for the DB engine.** 3. The central metric for Performance Insights is DB Session, which represents the average number of active sessions for the DB engine. 4. **You can visualize the database load and filter the load by waits, SQL statements, hosts, or users.**

Answer 70

1. Publicly Accessible property of the instance should be set to No. 2. **Publicly Accessible property of the instance should be set to Yes.** 3. **The RDS DB instance is in a state other than available, so it can't accept connections.** 4. **The source you use to connect to the instance is missing from the sources authorized to access the RDS DB instance in your security group, network ACLs, or local firewalls.** 5. **The incorrect DNS name or endpoint was used to connect to the DB instance.** 6. **The Multi-AZ instance failed over, and the secondary instance uses a subnet or route table that doesn't allow inbound connections.** 7. **The user authentication is incorrect.**

Answer 71

1. Migrate MySQL to Amazon RDS with Multi-AZ for performance. 2. **Migrate MySQL to Amazon RDS with Multi-AZ for resiliency.** 3. **Enable Read Replicas on Amazon RDS and distribute read traffic for performance improvement.** 4. Enable Read Replicas on Amazon RDS and distribute read traffic for resiliency.

Answer 72

1. Amazon EBS 2. **Amazon ElastiCache** 3. **Amazon DynamoDB Accelerator (DAX)** 4. **Amazon CloudFront** 5. **AWS Greengrass** 6. **Route 53**

Answer 73

1. RDS 2. **DynamoDB** 3. **S3** 4. EC2 5. **SQS** 6. ELB

Answer 74

1. EC2 2. **EBS** 3. RDS 4. ElastiCache 5. Redshift 6. DynamoDB 7. **S3**

Answer 75

1. You can take DynamoDB snapshots and store it in S3. 2. You can enable Multi-AZ deployment of DynamoDB. 3. You can enable Read Replica of DynamoDB in different AZ. 4. **Data is automatically replicated across multiple Availability Zones in an AWS Region.**

Answer 76

1. ElastiCache 2. RDS 3. **DynamoDB** 4. Redshift

Answer 77

1. Amazon RDS 2. Amazon Redshift 3. Amazon Glacier 4. **Amazon DynamoDB**

Answer 78

1. **DynamoDB is a NoSQL database that supports key-value and document data models.** 2. **DynamoDB global tables replicate your data automatically across your choice of AWS Regions and automatically scale capacity to accommodate your workloads.** 3. **With DynamoDB, there are no servers to provision, patch, or manage, and no software to install, maintain, or operate.** 4. DynamoDB is a RDBMS database that supports key-value and document data models.

Answer 79

1. JSON 2. **String** 3. **Number** 4. **Binary**

Answer 80

1. **DynamoDB automatically spreads the data and traffic for your tables over a sufficient number of servers to handle your throughput and storage requirements, while maintaining consistent and fast performance.** 2. **All of your data is stored on solid state disks (SSDs) and automatically replicated across multiple Availability Zones in an AWS region, providing built-in high availability and data durability.** 3. Amazon DynamoDB does not provide on-demand backup capability. 4. **Amazon DynamoDB provides on-demand backup capability.**

Answer 81

1. Read After Write 2. **Eventually Consistent Reads** 3. **Strongly Consistent Reads** 4. Lazy Read

Answer 82

1. Reserved 2. **On-Demand** 3. **Provisioned** 4. Spot

Answer 83

1. Able to forecast capacity requirements to control costs. 2. **Creating new tables with unknown workloads.** 3. **Unpredictable application traffic.** 4. **Prefer the ease of paying for only what you use.**

Answer 84

1. **Ability to forecast capacity requirements to control costs.** 2. **Predictable application traffic**. 3. Unpredictable application traffic. 4. **Applications whose traffic is consistent or ramps gradually.**

Answer 85

1. **MongoDB** 2. MySQL 3. PostgreSQL 4. Redis

Answer 86

1. **A read capacity unit represents one strongly consistent read per second, or two eventually consistent reads per second, for an item up to 4 KB in size.** 2. A read capacity unit represents one strongly consistent read per second, or two eventually consistent reads per second, for an item up to 8 KB in size. 3. **Transactional read requests require two read capacity units to perform one read per second for items up to 4 KB.** 4. Transactional read requests require two read capacity units to perform one read per second for items up to 8 KB.

Answer 87

1. **If you perform a read operation on an item that does not exist, DynamoDB still consumes provisioned read throughput.** 2. If you perform a read operation on an item that does not exist, DynamoDB does not consumes provisioned read throughput. 3. **One read capacity unit represents one strongly consistent read per second, or two eventually consistent reads per second, for an item up to 4 KB in size.** 4. **Transactional read requests require two read capacity units to perform one read per second for items up to 4 KB.**

Answer 88

1. One write capacity unit represents one write per second for an item up to 2 KB in size. 2. Transactional write requests require 1 write capacity units to perform one write per second for items up to 2 KB. 3. **One write capacity unit represents one write per second for an item up to 1 KB in size.** 4. **Transactional write requests require 2 write capacity units to perform one write per second for items up to 1 KB.**

Answer 89

1. Amazon RDS 2. **Amazon DynamoDB** 3. Amazon Redshift 4. Amazon S3

Answer 90

1. **Perform strongly consistent reads of up to 24 KB per second** 2. Perform eventually consistent reads of up to 24 KB per second 3. **Perform eventually consistent reads of up to 48 KB per second** 4. **Perform transactional read requests of up to 12 KB per second.**

Answer 91

1. **Write up to 6 KB per second.** 2. Perform transactional write requests of up to 6 KB per second. 3. Write up to 3 KB per second. 4. **Perform transactional write requests of up to 3 KB per second.**

Answer 92

1. **Eventually consistent reads** 2. Strongly consistent reads 3. Eventually consistent write 4. Strongly consistent write

Answer 93

1. Amazon RDS 2. Amazon Redshift 3. **Amazon DynamoDB** 4. Amazon S3

Answer 94

1. **Partition key** 2. Global secondary key 3. Local secondary key 4. **Partition key and sort key**

Answer 95

1. **Global secondary index – An index with a partition key and sort key that can be different from those on the table.** 2. **Local secondary index – An index that has the same partition key as the table, but a different sort key.** 3. Global secondary index – An index with a partition key and sort key that can be same as those on the table. 4. Local secondary index – An index that has the same partition key as the table, but two different sort key.

Answer 96

1. Amazon RDS 2. Amazon Redshift 3. **Amazon DynamoDB** 4. Amazon S3

Answer 97

1. **You should start designing your schema only after you have understood business problems and the application use cases.** 2. You design for flexibility without worrying about implementation details or performance. 3. **You should maintain as few tables as possible in a DynamoDB application.** 4. **You design your schema specifically to make the most common and important queries as fast and as inexpensive as possible.**

Answer 98

1. **Manage Throughput Capacity Automatically with DynamoDB Auto Scaling** 2. **Use DAX which is in-memory cache for DynamoDB** 3. Use Internal Application Load Balancer with DynamoDB 4. Use EC2 auto scaling for DynamoDB.

Answer 99

1. **Item sizes** 2. **Expected read and write request rates** 3. **Read consistency requirement** 4. Write consistency requirement

Answer 100

1. Timestamp, Employeeid 2. **Employeeid, Timestamp** 3. Message, Employeename 4. Employeeid, message

Answer 101

1. DynamoDB Events 2. **DynamoDB Streams** 3. DynamoDB DAX 4. DynamoDB Triggers

Answer 102

1. An application in one AWS Region modifies the data in a DynamoDB table. A second application in another Region reads these data modifications and writes the data to another table, creating a replica that stays in sync with the original table. 2. A popular mobile app modifies data in a DynamoDB table, at the rate of thousands of updates per second. Another application captures and stores data about these updates, providing near-real-time usage metrics for the mobile app. 3. A global multi-player game has a multi-master topology, storing data in multiple AWS Regions. Each master stays in sync by consuming and replaying the changes that occur in the remote Regions. 4. **Tracking the session time inactivity for a website user and logging out it after pre-defined duration expiry.** 5. An application automatically sends notifications to the mobile devices of all friends in a group as soon as one friend uploads a new picture. 6. A new customer adds data to a DynamoDB table. This event invokes another application that sends a welcome email to the new customer.

Answer 103

1. Each read will require half provisioned read capacity unit. 2. You have to set the table's provisioned read throughput to 40 read capacity units. 3. **Each read will require one provisioned read capacity unit.** 4. **You have to set the table's provisioned read throughput to 80 read capacity units.**

Answer 104

1. **A global secondary index is considered "global" because queries on the index can span all of the data in the base table, across all partitions.** 2. A global secondary index is considered "global" because queries on the index cannot span all of the data in the base table, across all partitions. 3. **A local secondary index is "local" in the sense that every partition of a local secondary index is scoped to a base table partition that has the same partition key value.** 4. A local secondary index is "local" in the sense that every partition of a local secondary index is scoped to a base table partition that has the different partition key value.

Answer 105

1. **Queries on global secondary indexes support eventual consistency only.** 2. Every local secondary index has its own provisioned throughput settings for read and write activity. 3. **When you query a local secondary index, you can choose either eventual consistency or strong consistency.** 4. **Every global secondary index has its own provisioned throughput settings for read and write activity.** 5. **Queries or scans on a local secondary index consume read capacity units from the base table.**

Answer 106

1. Each write will require half provisioned write capacity unit. 2. You have to set the table's provisioned throughput to 50 write capacity units. 3. **Each write will require one provisioned write capacity unit.** 4. **You have to set the table's provisioned write throughput to 100 write capacity units.**

Answer 107

1. **DAX is a DynamoDB-compatible caching service that enables you to benefit from fast in-memory performance.** 2. DAX is a DynamoDB-compatible auto scaling service that enables you to benefit from fast in-memory performance. 3. **DAX is suitable for use case where you have applications that are read-intensive, but are also cost-sensitive.** 4. **DAX is suitable for use case where you have applications that require repeated reads against a large set of data.**

Answer 108

1. **A query that specified the key attributes (UserId and GameTitle) would be very efficient for a leaderboard application to display top scores for each game for a given userid.** 2. A query that specified the key attributes (UserId and GameTitle) would be very inefficient for a leaderboard application to display top scores for each game for a given userid. 3. **If the application needed to retrieve data from GameScores based on GameTitle only, it would need to use a Scan operation.** 4. If the application needed to retrieve data from GameScores based on GameTitle only, it would need to use a Query operation.

Answer 109

1. No change required, the table design will work efficiently for retrieving required data. 2. **Create a global secondary index with attributes, partition key of GameTitle and a sort key of TopScore.** 3. Create a global secondary index with attributes, partition key of GameTitle and a sort key of UserID. 4. Create a global secondary index with attributes, partition key of UserID and a sort key of GameTitle.

Answer 110

1. Create new instances of DynamoDB and other application layer which caters only to North American user for one month. 2. Increase the provisioned capacity of DynamoDB tables during day time and decrease it during night 3. **Use DynamoDB auto scaling to dynamically adjust provisioned throughput capacity on your behalf, in response to actual traffic patterns.** 4. Create more secondary indexes for every table to optimize the query performance

Answer 111

1. **When a new item is added to the table, the stream captures an image of the entire item, including all of its attributes.** 2. **When an item is updated in the table, the stream captures the "before" and "after" image of any attributes that were modified in the item.** 3. When an item is updated in the table, the stream captures only the “after" image of any attributes that were modified in the item. 4. **When an item is deleted from the table, the stream captures an image of the entire item before it was deleted.**

Answer 112

1. **Applications that require the fastest possible response time for reads.** 2. **Applications that read a small number of items more frequently than others.** 3. Applications that are write-intensive, or that do not perform much read activity. 4. **Applications that are read-intensive, but are also cost-sensitive.** 5. **Applications that require repeated reads against a large set of data.**

Answer 113

1. **The partition key and sort key of the table are always projected into the index.** 2. **You can project other attributes apart from partition and sort key.** 3. Only the partition key of the table is projected into the index. 4. Only the sort key of the table is projected into the index. 5. You can project maximum of three attributes apart from partition and sort key.

Answer 114

1. Memcached only 2. Redis Only 3. **Memcached and Redis** 4. Varnish 5. Varnish, Memcached and Redis

Answer 115

1. **Enable Time to Live on the session data table.** 2. Write a program which continuously reads the table entries and deletes records which are expired. 3. Write a program which runs every two hours, reads the table entries and deletes records which are expired. 4. Write a stored procedure which deletes records which are more than two hours old.

Answer 116

1. **Applications that require strongly consistent reads.** 2. **Applications that do not require microsecond response times for reads, or that do not need to offload repeated read activity from underlying tables.** 3. **Applications that are write-intensive, or that do not perform much read activity.** 4. **Applications that are already using a different caching solution with DynamoDB, and are using their own client-side logic for working with that caching solution.** 5. Application that require eventually consistent reads.

Answer 117

1. **Amazon ElastiCache** 2. Amazon Neptune 3. Amazon DynamoDB 4. Amazon DocumentDB

Answer 118

1. Memcached supports transactions which let you execute a group of commands as an isolated and atomic operation. Redis does not. 2. **Memcached is multithreaded and Redis is not.** 3. **Redis supports snapshots and replications. Memcached does not.** 4. **Redis has geospatial support, Memcached does not.**

Answer 119

1. **Amazon ElastiCache for Redis** 2. Amazon ElastiCache for Memcached 3. Amazon DynamoDB 4. Amazon S3

Answer 120

1. **It is slow or expensive to acquire when compared to cache retrieval.** 2. **It is accessed with sufficient frequency.** 3. It is dynamic, or if rapidly changing, it should be real time value. 4. **It is relatively static, or if rapidly changing, staleness is not a significant issue.**

Answer 121

1. **Lazy loading strategy that loads data into the cache only when necessary.** 2. **Write through strategy adds data or updates data in the cache whenever data is written to the database.** 3. Periodic time based refreshing of whole data in the cache. 4. **Adding a time to live (TTL) value to each write.**

Answer 122

1. **You need the simplest model possible.** 2. You need complex data types, such as strings, hashes, lists, sets, sorted sets, and bitmaps. 3. **You need to run large nodes with multiple cores or threads.** 4. **You need the ability to scale out and in, adding and removing nodes as demand on your system increases and decreases. You need to cache objects, such as a database.**

Answer 123

1. No change required in the current table design. 2. Create a local secondary index having partition key with Subject, but with sort key as LastPostDateTime. 3. Create a local secondary index having partition key with LastPostDateTime, but with sort key as Subject. 4. **Create a local secondary index having partition key same as that of the Thread table, but with sort key as LastPostDateTime.**

Answer 124

1. **User ID, where the application has many users.** 2. Status code, where there are only a few possible status codes. 3. Item creation date, rounded to the nearest time period (for example, day, hour, or minute). 4. **Device ID, where each device accesses data at relatively similar intervals.** 5. Device ID, where even if there are many devices being tracked, one is by far more popular than all the others.

Answer 125

1. By serving high-volume application read traffic. 2. **By caching the database query results.** 3. By delivering up to a 10x performance improvement – from milliseconds to microseconds – even at millions of requests per second. 4. By securely delivering data, videos, applications, and APIs to customers globally with low latency, high transfer speed.

Answer 126

1. **Use Lambda with DynamoDB stream to capture the new post or topic record insertion in the table, function will have logic to query the list of users subscribed to that discussion topic then it will send notification to subscribed users through SNS.** 2. Use Cloudwatch with DynamoDB stream to capture the new post or topic record insertion in the table, trigger a Lambda to query the list of users subscribed to that discussion topic then it will send notification to subscribed users through SNS. 3. Use Cloudtrail with DynamoDB stream to capture the new post or topic record insertion in the table, trigger a Lambda to query the list of users subscribed to that discussion topic then it will send notification to subscribed users through SNS. 4. Use a scheduled job running in an EC2 server to continuously read the DynamoDB table and send the notification to subscribed users through SNS.

Answer 127

1. **You need complex data types, such as strings, hashes, lists, sets, sorted sets, and bitmaps.** 2. **You need to sort or rank in-memory datasets. You need persistence of your key store.** 3. **You need to replicate your data from the primary to one or more read replicas for read intensive applications.** 4. You need to store object data types only.

Answer 128

1. You don’t need automatic failover if your primary node fails. 2. **You need automatic failover if your primary node fails.** 3. **You need publish and subscribe (pub/sub) capabilities—to inform clients about events on the server.** 4. **You need backup and restore capabilities. You need to support multiple databases.**

Answer 129

1. **Automatic detection and recovery from cache node failures.** 2. **Multi-AZ with automatic failover of a failed primary cluster to a read replica in Redis clusters that support replication.** 3. Multi-AZ with automatic failover of a failed primary cluster to a standby instance in Redis clusters that support replication. 4. **Redis (cluster mode enabled) supports partitioning your data across up to 90 shards.** 5. **Starting with Redis version 3.2.6, all subsequent supported versions support in-transit and at-rest encryption with authentication so you can build HIPAA-compliant applications**

Answer 130

1. **Node** 2. **Shards** 3. **Cluster** 4. Threads

Answer 131

1. **1 shard** 2. 1-30 shards 3. 1-60 shards 4. 1-90 shards

Answer 132

1. 1 shard 2. 1-30 shards 3. 1-60 shards 4. **1-90 shards**

Answer 133

1. **Distribute read and write operations as evenly as possible across your table.** 2. Enable Adaptive capacity to run imbalanced workloads indefinitely. 3. **Use DynamoDB Auto Scaling with reserved capacity.** 4. Use On-demand capacity mode.

Answer 134

1. Use Cloudfront with DynamoDB as origin 2. **Enable DynamoDB Accelerator (DAX) and DynamoDB auto scaling** 3. **Use DynamoDB Global Tables** 4. Enable DynamoDB Adaptive Capacity

Answer 135

1. Your VPC must have at least two subnets. These subnets must be in two different Availability Zones in the AWS Region where you want to deploy your DB instance. 2. If you want your DB instance in the VPC to be publicly accessible, you must enable the VPC attributes DNS hostnames and DNS resolution. 3. You create a DB subnet group by specifying the subnets you created. Amazon RDS uses that DB subnet group and your preferred Availability Zone to choose a subnet and an IP address within that subnet to assign to your DB instance. 4. **Your VPC must have at least three subnets. These subnets must be in three different Availability Zones in the AWS Region where you want to deploy your DB instance.** 5. **If you want your DB instance in the VPC to be publicly accessible, you must enable the RDS attributes DNS hostnames and DNS resolution.**

Answer 136

1. **A shard (API/CLI: node group) is a collection of one to six Redis nodes.** 2. A Redis (cluster mode enabled) cluster will never have more than one shard. 3. **Redis (cluster mode enabled) clusters can have from 1 to 90 shards.** 4. **A Redis (cluster mode disabled) cluster will never have more than one shard.**

Answer 137

1. **With a single shard that contains all of the cluster's data in each node—Redis cluster mode disabled** 2. **With data partitioned across up to 90 shards—Redis cluster mode enabled** 3. With a single shard that contains all of the cluster's data in each node—Redis cluster mode enabled 4. With data partitioned across up to 90 shards—Redis cluster mode disabled

Answer 138

1. 90 replicas and 0 shards 2. **90 shards and 0 replicas** 3. **15 shards and 5 replicas** 4. 5 shards and 0 replicas

Answer 139

1. **Application Load Balancer, RDS Multi-AZ & Read Replica, Web EC2 Instance Auto Scale Multi AZ, ElastiCache, Cloudfront, S3** 2. Application Load Balancer, RDS , Web EC2 Instance Auto Scale Multi AZ, DynamoDB, ElastiCache, Cloudfront, S3 3. Application Load Balancer, RDS Multi-AZ & Read Replica, Web EC2 Instance Auto Scale Multi AZ, S3 4. Application Load Balancer, RDS, Web EC2 Instance Auto Scale Multi AZ, DynamoDB, ElastiCache, Cloudfront, S3

Answer 140

1. ElastiCache for Memcache 2. **ElastiCache for Redis** 3. RDS 4. DynamoDB

Answer 141

1. With a single shard that contains all of the cluster's data in each node—Redis cluster mode enabled 2. With data partitioned across up to 90 shards—Redis cluster mode disabled 3. **With a single shard that contains all of the cluster's data in each node—Redis cluster mode disabled** 4. **With data partitioned across up to 90 shards—Redis cluster mode enabled**

Answer 142

1. **It has a single shard, inside of which is a collection of Redis nodes; one primary read/write node and up to five secondary, read-only replica nodes.** 2. **Each read replica maintains a copy of the data from the cluster's primary node. Asynchronous replication mechanisms are used to keep the read replicas synchronized with the primary.** 3. **Applications can read from any node in the cluster. Applications can write only to the primary node.** 4. **Read replicas improve read throughput and guard against data loss in cases of a node failure.** 5. Each read replica maintains a part of the data from the cluster's primary node. Synchronous replication mechanisms are used to keep the read replicas synchronized with the primary.

Answer 143

1. **Cluster is comprised of from 1 to 90 shards (API/CLI: node groups). Each shard has a primary node and up to five read-only replica nodes.** 2. **The configuration can range from 90 shards and 0 replicas to 15 shards and 5 replicas, which is the maximum number or replicas allowed.** 3. **Data is partitioned across the shards.** 4. Each shard contains full copy of the data, data is not partitioned across the shards. 5. **Each read replica in a shard maintains a copy of the data from the shard's primary. Asynchronous replication mechanisms are used to keep the read replicas synchronized with the primary.**

Answer 144

1. Availability and Resiliency 2. **Scaling v. partitioning** 3. **Node size v. number of nodes** 4. **Reads v. writes**

Answer 145

1. **Redis (cluster mode disabled)** 2. Redis (cluster mode enabled)

Answer 146

1. Redis (cluster mode disabled) 2. **Redis (cluster mode enabled)**

Answer 147

1. Amazon RDS 2. **Amazon DynamoDB** 3. **Amazon DocumentDB** 4. Amazon Aurora

Answer 148

1. **1-20 nodes** 2. 1-10 nodes 3. 1-100 nodes 4. 1-90 nodes

Answer 149

1. The ability for client programs to automatically identify primary node in the cluster. 2. Your application does not need to manually connect to individual cache nodes; instead, your application connects to one primary Memcached node. 3. **The ability for client programs to automatically identify all of the nodes in a cache cluster, and to initiate and maintain connections to all of these nodes.** 4. **Your application does not need to manually connect to individual cache nodes; instead, your application connects to one Memcached node and retrieves the list of nodes.**

Answer 150

1. **Update application's Memcached config file to include the endpoints of the servers (nodes).** 2. Recompile and re-linking application as the libraries currently used will not continue to work. 3. **Switch to using Amazon ElastiCache without recompiling or re-linking your applications - the libraries currently being used will continue to work.** 4. You can migrate your application after making code changes as Amazon ElastiCache is not protocol-compliant with Memcached.

Answer 151

1. On adding new nodes, update the list of cache node endpoints manually in the configuration file and re-initialize the application by restarting it. 2. **Auto Discovery capable client must be used to connect to Amazon ElastiCache Cluster.** 3. Auto Discovery capable server must be used to connect to Amazon ElastiCache Cluster. 4. None of the above

Answer 152

1. Key value: DynamoDB 2. Document: DocumentDB 3. **Relational: RDS** 4. Graph: Neptune 5. In-memory: ElastiCache 6. Search: Elasticsearch

Answer 153

1. RDS instance in different AWS regions with Multi-AZ deployment 2. **DynamoDB with Global Tables** 3. S3 with cross region replication 4. Database deployed in EC2 instances with EBS volumes

Answer 154

1. **Create a snapshot of the unencrypted database instance.** 2. **Copy the snapshot to a new, encrypted snapshot. Enable encryption and specify the desired KMS key as you do so.** 3. **Create a new database instance with encryption enabled.** 4. Copy the data from existing to new database. 5. Restore the encrypted snapshot to a new database instance

Answer 155

1. Multi-AZ with Automatic Failover 2. Daily automatic backups 3. Manual backups using Redis append-only file (AOF) 4. **All of the above**

Answer 156

1. **ElastiCache detects the failed read replica.** 2. **ElastiCache takes the failed node off line.** 3. **ElastiCache launches and provisions a replacement node in the same AZ.** 4. ElastiCache launches and provisions a replacement node in the same or different AZ. 5. **The new node synchronizes with the one of most updated Read Replica.** 6. The new node synchronizes with the Primary node.

Answer 157

1. **Enabled: ElastiCache promotes the read replica node with the least replication lag to primary node, the other replicas sync with the new primary node and new replica is created in failed primary’s AZ.** 2. Disabled: ElastiCache promotes the read replica node with the least replication lag to primary node, the other replicas sync with the new primary node and new replica is created in failed primary’s AZ. 3. Enabled: ElastiCache creates and provisions a new Primary node to replace the failed Primary and syncs the new Primary with one of the existing replicas. 4. **Disabled: ElastiCache creates and provisions a new Primary node to replace the failed Primary and syncs the new Primary with one of the existing replicas.**

Answer 158

1. **Content management applications such as blogs and video platforms.** 2. **For storing catalog information such as in an e-commerce application.** 3. Real-time bidding applications such as buying and selling of online ad impressions. 4. Gaming leaderboard shows a gamer's position relative to other players of a similar rank.

Answer 159

1. **Compatible with MongoDB 3.6 drivers and tools.** 2. Compatible with DynamoDB 3.6 drivers and tools. 3. **Automatically grows the size of your storage volume as your database storage needs grow. Your storage volume grows in increments of 10 GB, up to a maximum of 64 TB.** 4. **You can increase read throughput to support high-volume application requests by creating up to 15 replica instances.** 5. You can increase write throughput to support high-volume application requests by creating up to 15 replica instances. 6. **Automates failover to one of up to 15 Amazon DocumentDB replicas you have created in any of three Availability Zones. If no Amazon DocumentDB replicas have been provisioned, in the case of a failure, Amazon DocumentDB will attempt to create a new instance for you automatically.** 7. **Each 10GB portion of your storage volume is replicated six ways, across three Availability Zones.**

Answer 160

1. **Cluster volume** 2. Writer Volume 3. Reader Volume 4. **Instances**

Answer 161

1. If you do not have an Amazon DocumentDB replica, you will need to create a new one manually in the same or a different Availability Zone, then flip the canonical name record (CNAME) for your cluster endpoint to new instance. 2. **If you have an Amazon DocumentDB replica, in the same or a different Availability Zone, when failing over, Amazon DocumentDB flips the canonical name record (CNAME) for your cluster endpoint to a healthy replica, which is in turn is promoted to become the new primary.** 3. **If you do not have an Amazon DocumentDB Replica (i.e. single instance), Amazon DocumentDB will first attempt to create a new instance in the same Availability Zone as the original instance. If unable to do so, Amazon DocumentDB will attempt to create a new instance in a different Availability Zone.** 4. If you have an Amazon DocumentDB Replica, Amazon DocumentDB will first attempt to create a new instance in the same Availability Zone as the original instance. If unable to do so, Amazon DocumentDB will attempt to create a new instance in a different Availability Zone.