AWS Certified Solutions Architect Associate (SAA02) – Free Practice Tests

Explanation

Don’t use your AWS root account credentials to access AWS, and don’t give your credentials to anyone else. Instead, create individual users for anyone who needs access to your AWS account. Create an IAM user for yourself as well, give that user administrative privileges, and use that IAM user for all your work.

Explanation

When creating an alarm, select a period that is greater than or equal to the frequency of the metric to be monitored. For example, basic monitoring for Amazon EC2 provides metrics for your instances every 5 minutes. When setting an alarm on a basic monitoring metric, select a period of at least 300 seconds (5 minutes). Detailed monitoring for Amazon EC2 provides metrics for your instances every 1 minute. When setting an alarm on a detailed monitoring metric, select a period of at least 60 seconds (1 minute).

Explanation

In Amazon Web Services, the spot instance is useful when the user wants to run a process temporarily. The spot instance can terminate the instance if the other user outbids the existing bid. In this case all storage is temporary and the data is not required to be persistent. Thus, the spot instance is a good option to save money

Explanation

A Geolocation routing policy would allow Route 53 to route queries based upon the location of users. DynDNS is used to automatically update DNS records. EDNS0 can be used to improve the accuracy of geolocation routing, but is not a routing policy in and of itself. Region based is not a valid Route 53 routing policy type.

Explanation

Explanation

For an EC2 instance launched with an EBS backed Windows AMI, each time the instance state is changed from stop to start/ running, AWS charges restart a new per-hour charge. Effective October 2, 2017, charges are calculated on a per-second basis for On-Demand, Spot and Reserved instances with Linux operating systems, with a minimum one-minute charge. Regardless of operating system, rebooting an instance AWS does not incur a charge an hour or one-minute minimum charge.

Explanation

Using IAM, you apply permissions to IAM users, groups, and roles by creating policies. You can create two types of IAM policies: Managed Policies and Inline Policies. Managed policies are standalone policies that you can attach to multiple users, groups, and roles in your AWS account. Managed policies apply only to identities (users, groups, and roles) – not resources. Inline policies are policies that you create and manage, and that are embedded directly into a single user, group, or role.

Explanation

The charge for successful Requester Pays requests is straightforward: the requester pays for the data transfer and the request; the bucket owner pays for the data storage. However, the bucket owner is charged for the anonymous request.

Explanation

S3 bucket access control lists are a legacy access control mechanism, created before IAM existed. S3 bucket ACLs are best used for a limited set of use cases

Explanation

For increased security, AWS recommends that you configure multi-factor authentication (MFA) to help protect your AWS resources. MFA adds extra security because it requires users to enter a unique authentication code from an approved authentication device or SMS text message when they access AWS websites or services. This type of MFA requires you to assign an MFA device (hardware or virtual) to the IAM user or the AWS root account.

Explanation

For the SSH agent forwarding to be successful, both security groups need to allow connection via port 22. Custom security groups by default allow all outbound traffic, but deny all inbound traffic.

Explanation

The user may want to stop the automated scaling processes on the Auto Scaling groups either to perform manual operations or during emergency situations. To perform this, the user can suspend one or more scaling processes at any time. Once it is completed, the user can resume all the suspended processes.

Explanation

Trusted Advisor checks for Amazon EC2 reserved instances optimization, low utilization of Amazon EC2 instances, idle Load Balancers, underutilized Amazon EBS Volumes, unassociated Elastic IP Addresses, Amazon RDS idle DB instances, Amazon Route 53 Latency Resource Record Sets, Amazon EC2 reserved instance lease expiration and underutilized Amazon Redshift Clusters

Explanation

Each CloudWatch alarm watches a single metric and sends messages to Auto Scaling when the metric breaches a threshold that you specify in your policy. Changing the scale down the CloudWatch metric to a higher threshold will not cost any more.

Auto Scaling also supports adding life-cycle hooks to Auto Scaling groups. These hooks enable you to control how instances launch and terminate within an Auto Scaling group; you can perform actions on the instance before it is put into service or before it is terminated. This is also cost-efficient and hence also a correct answer.

All the other answers will not optimize costs.

Explanation

A VPC peering connection is a networking connection between two VPCs that enables you to route traffic between them using private IPv4 addresses or IPv6 addresses. Instances in either VPC can communicate with each other as if they are within the same network. You can create a VPC peering connection between your own VPCs, or with a VPC in another AWS account.

Explanation

The Elastic Load Balancer can integrate with the AWS Certificate Manager to provide a central method of managing your TLS/SSL certificates. It allows you to renew, deploy and configure your TLS/SSL certificates for your application or website from a single location.

Explanation

An Amazon Machine Image (AMI) is a template that contains a software configuration (for example, an operating system, an application server, and applications). The AMI includes the operating system, initial state of any patches, and any application software. For example, you can select an AMI that has SQL Server. The virtual CPUs are not part of the AMI but are defined by the instance type.

Explanation

Auto scaling provides redundancy for a single server with the option of launching a configuration using the attributes from a running instance. When you use this option, auto scaling copies the attributes from the specified instance into a template from which you can launch one or more auto scaling groups.

Explanation

EC2 instance store volumes can be added as additional volumes to certain EBS-backed EC2 Instance types. Any data on the instance store volumes persists as long as the instance is running, but this data is deleted when the instance is terminated or if it fails (such as if an underlying drive has issues).

Explanation

When scaling a database, you can increase the storage capacity of a DB Instance up to a maximum of 64 terabytes (TiB). Please note that scaling the storage allocation with Amazon RDS does not incur a database outage. The performance will be increased as well.

Explanation

When an Amazon EBS-backed instance is stopped, you’re not charged for instance usage; however, you’re still charged for volume storage. Amazon charges a full instance hour for every transition from a stopped state to a running state, even if you transition the instance multiple times within a single hour. In this scenario, the charge was $42, which is three times more than $14. This suggests that you stopped and restarted that instance twice during that hour (the initial $14, plus 2 x $14 for each restart).

Although some instances now have per-second billing available, this new billing structure does not apply to Windows instances at this point.

Explanation

S3 Event Notifications can be set up on objects stored in S3. An event could be set up to notify when a delete is performed. Logging is turned off by default but can be enabled. When enabled, they can track requests to your S3 bucket.

S3 Server Access Logging tracks detailed information not currently available with CloudWatch metrics or CloudTrail logs. To track requests for access to your bucket, you can enable access logging. Each access log record provides details about a single access request, such as the requester, bucket name, request time, request action, response status, and error code, if any. Access log information can be useful in security and access audits. It can also help you learn about your customer base and understand your Amazon S3 bill.

Explanation

You can associate more than one scaling policy with an autoscaling group. Having one policy to scale out and one policy to scale in is a viable option. Scaling out during business hours and scaling in during off hours could be fairly effective for performance and cost. But scaling out and in using CloudWatch metrics for CPU utilization would be much more precise for both performance and cost considerations.

Explanation

By tagging all resources with the business unit and enabling detailed billing reports, you would enable the finance team to run cost reports by business unit.

Explanation

An EBS volume is off-instance storage that can persist independently from the life of an instance. You continue to pay for the volume usage as long as the data persists. EBS instances can be stopped and re-started. And EBS volumes boot faster than instance store volumes often by an order of magnitude

Explanation

When creating an alarm, select a period that is greater than or equal to the frequency of the metric to be monitored. For example, basic monitoring for Amazon EC2 provides metrics for your instances every 5 minutes. When setting an alarm on a basic monitoring metric, select a period of at least 300 seconds (5 minutes). Detailed monitoring for Amazon EC2 provides metrics for your instances every 1 minute. When setting an alarm on a detailed monitoring metric, select a period of at least 60 seconds (1 minute).

Explanation

Instances that you launch into a default subnet receive both a public IP address and a private IP address. Instances in a default subnet also receive both public and private DNS hostnames. Instances that you launch into a nondefault subnet in a default VPC don’t receive a public IP address or a DNS hostname. You can change your subnet’s default public IP addressing behavior

Explanation

FGAC can benefit any application that tracks information in a DynamoDB table, where the end user (or application client acting on behalf of an end user) wants to read or modify the table directly, without a middle-tier service. For instance, a developer of a mobile app named Acme can use FGAC to track the top score of every Acme user in a DynamoDB table. FGAC allows the application client to modify only the top score for the user that is currently running the application

Explanation

A Virtual Private Cloud (VPC) is a virtual network dedicated to the user’s AWS account. A user can create a subnet with VPC and launch instances inside that subnet. When the user is launching an instance he needs to select an option which attaches a public IP to the instance. If the user has not selected the option to attach the public IP, then it will only have a private IP when launched. If the user wants to connect to an instance from the Internet, he should create an elastic IP with VPC. If the elastic IP isa part of EC2 Classic, it cannot be assigned to a VPC instance.

Explanation

Each subnet must be associated with a route table, which controls the routing for the subnet. If you don’t explicitly associate a subnet with a particular route table, the subnet is implicitly associated with the main route table. A route in the route table to an Internet Gateway marks the subnet as a public subnet and no route to an Internet Gateway marks the subnet as private.

Explanation

If you have multiple VPN connections, you can provide secure communication between sites using the AWS VPN CloudHub. The VPN CloudHub operates on a simple hub-and-spoke model that you can use with or without a VPC. This design is suitable for customers with multiple branch offices and existing Internet connections who’d like to implement a convenient, potentially low-cost hub-and-spoke model for primary or backup connectivity between these remote offices. To use the AWS VPN CloudHub, you must create a virtual private gateway with multiple customer gateways, each with unique Border Gateway Protocol (BGP) Autonomous System Numbers (ASNs). Customer gateways advertise the appropriate routes (BGP prefixes) over their VPN connections. These routing advertisements are received and re-advertised to each BGP peer, enabling each site to send data to and receive data from the other sites. The routes for each spoke must have unique ASNs and the sites must not have overlapping IP ranges. Each site can also send and receive data from the VPC as if they were using a standard VPN connection

Explanation

The Total Cost of Ownership (TCO) Calculator is a free service offered by AWS to allow you to compare the cost of on-premises servers and AWS cloud services. It requires users to answer a short series of questions and then provides a detailed report on the potential AWS cloud environment that would mirror their on-premise systems.

Explanation

Auto Scaling uses EC2 status checks to detect hardware and software issues with the instances, but the load balancer performs health checks by sending a request to the instance and then waiting for a 200 response code, or by establishing a TCP connection (for a TCP-based health check) with the instance. Even if you’ve configured an Elastic Load Balancer, the autoscaler does not automatically check the ELBs health checks. You must add the ELB Health Check to your autoscaling policy.

Explanation

In Hybrid cloud environment where connectivity between AWS and Corporate datacenter is critical, redundant active/active or active/passive configurations should be implemented for connectivity resources. redundancy has to be on both sides (AWS and On-premises) hence the minimum requirements to implement this architecture is two direct connect lines and two customer devices (ideally in two different data centers)

Explanation

Explanation

Amazon EBS provides three volume types: General Purpose SSD, Provisioned IOPS SSD, and Magnetic.

General Purpose SSD volumes are the default EBS volume type for Amazon EC2 instances.

GP2 volumes smaller than 1 TB can burst up to 3,000 IOPS. I/O is included in the price of gp2, so you pay only for each GB of storage you provision. GP2 is designed to deliver the provisioned performance 99% of the time. If you need a greater number of IOPS than gp2 can provide, or if you have a workload where low latency is critical or you need better performance consistency, we recommend that you use io1.

Explanation

Amazon CloudWatch Alarms have three possible states: OK: The metric is within the defined threshold ALARM: The metric is outside of the defined threshold INSUFFICIENT_DATA: The alarm has just started, the metric is not available, or not enough data is available for the metric to determine the alarm state

Explanation

These types of issues can be investigated in a checklist type manner. First, it’s important to verify manually that the EC2 instances are properly functioning. If so, it becomes a network issue. Are the Security Groups configured properly? Are the ACLs configured properly? Once the instances are verified, it is most likely that a Security Group or ACL is not configured properly.

Explanation

Implementing a Route 53 Calculated Health Check is the best solution in this case because it aggregates all of the individual health checks. Integrating QuickSight and CloudTrail will create an effective dashboard, but this is not an automated solution because someone has to continuously check the dashboard.

You can also create a CloudWatch Log log alarm, but this would be overly complex compared to the Calculated Health Checks.

For example, let’s say you have deployed 15 EC2 instances, and created 15 separate Route 53 health checks to monitor each one. While you are concerned about each instance’s performance, you essentially need 10 of the 15 instances to be healthy for your system to run properly. Rather than setting up SNS notifications for each individual health check, you can create a calculated health check that collects the results of each health check into a single count between 0-15, and compares that count to a threshold you’ve set. In this case, the threshold could be 10. Now, if 10 instances are healthy, the calculated health check comes back healthy. If less than 10 instances are healthy, the health check comes back unhealthy.For example, let’s say you have deployed 15 EC2 instances, and created 15 separate Route 53 health checks to monitor each one. While you are concerned about each instance’s performance, you essentially need 10 of the 15 instances to be healthy for your system to run properly. Rather than setting up SNS notifications for each individual health check, you can create a calculated health check that collects the results of each health check into a single count between 0-15, and compares that count to a threshold you’ve set. In this case, the threshold could be 10. Now, if 10 instances are healthy, the calculated health check comes back healthy. If less than 10 instances are healthy, the health check comes back unhealthy.

Explanation

A VPC peering connection is a networking connection between two VPCs that enables you to route traffic between them using private IPv4 addresses or IPv6 addresses. Instances in either VPC can communicate with each other as if they are within the same network. You can create a VPC peering connection between your own VPCs, or with a VPC in another AWS account.

Explanation

For the SSH agent forwarding to be successful, both security groups need to allow connection via port 22. Custom security groups by default allow all outbound traffic, but deny all inbound traffic.

Explanation

Auto Scaling can start and stop the instance at a pre-defined time. Here, the total running time is unknown. Thus, the user has to use the CloudWatch alarm, which monitors the CPU utilization. The user can create an alarm that is triggered when the average CPU utilization percentage has been lower than 10 percent for 24 hours, signaling that it is idle and no longer in use. When the utilization is below the threshold limit, it will terminate the instance as a part of the instance action.

Explanation

In AWS CloudFormation, Amazon EC2 resources that support the tagging feature can also be tagged in an AWS template. The tag values can refer to template parameters, other resource names, resource attribute values (e.g. addresses), or values computed by simple functions (e.g., a concatenated list of strings).

Explanation

Amazon Relational Database Service (Amazon RDS) is a managed service that makes it easy to set up, operate, and scale a relational database in the cloud. It provides cost-efficient and resizable capacity, while managing time-consuming database administration tasks, freeing you up to focus on your applications and business. When you create or modify your DB Instance to run as a Multi-AZ deployment, Amazon RDS automatically provisions and maintains a synchronous “standby” replica in a different Availability Zone. Updates to your DB Instance are synchronously replicated across Availability Zones to the standby in order to keep both in sync and protect your latest database updates against DB Instance failure. During certain types of planned maintenance, or in the unlikely event of DB Instance failure or Availability Zone failure, Amazon RDS will automatically failover to the standby so that you can resume database writes and reads as soon as the standby is promoted. Since the name record for your DB Instance remains the same, your application can resume database operation without the need for manual administrative intervention. With Multi-AZ deployments, replication is transparent: you do not interact directly with the standby, and it cannot be used to serve read traffic. If you are using Amazon RDS for MySQL and are looking to scale read traffic beyond the capacity constraints of a single DB Instance, you can deploy one or more Read Replicas

Explanation

Amazon Route 53 lets you configure DNS failover in active-active, active-passive, and mixed configurations to improve the availability of your application. When you have more than one resource performing the same function, you can configure Amazon Route 53 to check the health of your resources and respond to DNS queries using only the healthy resources.

Another solution would be to assign an elastic IP address to the EC2 instance and have a backup instance running. In the event of failure, move the Elastic IP from the primary instance to the backup instance.

Explanation

You can place a network interface on each of your web servers that connects to a mid-tier network where an application server resides. The application server can also be dual-homed to a back-end network (subnet) where the database server resides. Instead of routing network packets through the dual-homed instances, each dual-homed instance receives and processes requests on the front end, initiates a connection to the back end, and then sends requests to the servers on the back-end network.

Explanation

As your needs change, you might find that your instance is over-utilized (the instance type is too small) or under-utilized (the instance type is too large). If the root device for your instance is an Elastic Block Store (EBS) volume, you can change the size of the instance simply by changing its instance type, which is known as resizing it. If the root device for your instance is an instance store volume, you must migrate your application to a new instance with the instance type that you want

Explanation

Amazon VPC provides two features that you can use to increase security for your VPC: Security groups–Act as a firewall for associated Amazon EC2 instances, controlling both inbound and outbound traffic at the instance level. Network access control lists (ACLs)–Act as a firewall for associated subnets, controlling both inbound and outbound traffic at the subnet level. Security groups are stateful: (Return traffic is automatically allowed, regardless of any rules) Network ACLs are stateless: (Return traffic must be explicitly allowed by rules)

Explanation

Instances associated with a security group can’t talk to each other unless you add rules allowing it (exception: the default security group has these rules by default). By default, a security group includes an outbound rule that allows all outbound traffic. You can remove the rule and add outbound rules that allow specific outbound traffic only. If your security group has no outbound rules, no outbound traffic is allowed.

Explanation

Don’t use your AWS root account credentials to access AWS, and don’t give your credentials to anyone else. Instead, create individual users for anyone who needs access to your AWS account. Create an IAM user for yourself as well, give that user administrative privileges, and use that IAM user for all your work.

Explanation

Amazon EC2 supports the following storage options: Amazon Elastic Block Store (Amazon EBS) Amazon EC2 Instance Store Amazon Simple Storage Service (Amazon S3) Reference:

Explanation

The spot instances are ideal for the data processing workload during non-business hours, and deducting those instances from your minimum workload requirements leaves roughly six instances that are running all day. Purchase six standard reserved instances to meet this need with the greatest discount. You can then schedule reserved instances to run during business hours to meet the increase, and on-demand instances to scale as needed while providing necessary availability.

Explanation

Explanation

Amazon EC2 allows the user to launch On-Demand instances. Auto Scaling offers automation which can scale up or down resources as per the configured policy.

To set up Auto Scaling, the organization must first create an AMI. The organization should set up bootstrapping for the AMI so that when the instance is launched, it will automatically start the app server and DB server.

The organization should also setup ELB with instances to distribute the incoming load. Auto Scaling should be configured to scale up and down based on the application load and not on a particular schedule.

Explanation

For Amazon Web Services, the reserved instance helps the user save money if the user is going to run the same instance for a longer period. Generally, if the user uses the instances around 30-40% annually it is recommended to use RI. Here as the instance runs only for 1 hour daily it is not recommended to have RI as it will be costlier. The user should use on-demand with EBS in this case.

Explanation

Amazon CloudWatch provides the functionality to graph the metric data generated either by the AWS services or the custom metric to make it easier for the user to analyse. The AWS CloudWatch console provides the option to change the granularity of a graph and zoom in to see data over a shorter time period. To zoom, the user has to click in the graph details pane, drag on the graph area for selection, and then release the mouse button.

Explanation

You can host a static website on Amazon S3. On a static website, individual web pages include static content. They may also contain client-side scripts. Because your storage on Amazon S3 is virtually unlimited you can scale infinitely. You also do not need to service dynamic content so a database is not needed.

Explanation

When you create a snapshot of a Throughput Optimized HDD (st1) or Cold HDD (sc1) volume, performance may drop as far as the volume’s baseline value while the snapshot is in progress. This behavior is specific to these volume types.

Explanation

Resource-based permissions are permissions you attach directly to a resource. Resource-level permissions refer to the ability to specify not just what actions users can perform, but which resources they’re allowed to perform those actions on. Resource-based policies are inline only, not managed. You can specify resource-based permissions for Amazon S3 buckets, Amazon Glacier vaults, Amazon SNS topics, Amazon SQS queues, and AWS Key Management Service encryption keys.

Explanation

Since the database is not located in the same location as the application servers, network latency and bandwidth could potentially be an issue

Explanation

Issues that are not first solved locally will not be solved by moving to the cloud. Moving to the cloud is not a silver bullet. If there are inherent problems in the existing architecture there is no guarantee that they will be solved by moving to the cloud. Try to resolve any issues locally before migrating your architecture (and its existing issues) to the cloud.

Explanation

By upgrading to a larger t2 instance, you not only improve baseline compute power, you also improve the ability to handle bursts. Each T2 instance receives CPU Credits continuously at a set rate depending on the instance size. These credits provide the ability to handle bursts. You can also create a RAID 0 to maximize utilization of instance resources.

Explanation

A placement group is a logical grouping of instances within a single Availability Zone. Cluster placement groups are recommended for applications that benefit from low network latency, high network throughput, or both. To provide the lowest latency, and the highest packet-per-second network performance for your cluster placement group, choose an instance type that supports enhanced networking

Explanation

You can use the infrequent access to reduce the cost of certain classes of objects, as well as send older objects to Glacier for archiving at a much lower cost.

Note that data transfer into S3 is always free. So if you want to reduce your cost, using Snowball might speed up moving large data sets however it will not reduce your cost

Explanation

A security group controls the access to a DB instance. It does so by allowing access to IP address ranges or Amazon EC2 instances that you specify. Amazon RDS uses DB security groups, VPC security groups, and EC2 security groups. In simple terms, a DB security group controls access to a DB instance that is not in a VPC, a VPC security group controls access to a DB instance inside a VPC, and an Amazon EC2 security group controls access to an EC2 instance and can be used with a DB instance.

Explanation

Lazy loading keeps the cache up to date based only on requests, which avoids filling up the cache needlessly, but if data is only written to the cache when there is a cache miss, data in the cache can become stale since there are no updates to the cache when data is changed in the database. This issue is addressed by using lazy loading in conjunction with write through, which adds data or updates data in the cache whenever data is written to the database. You may also use CloudFront to optimize your caching. By default, CloudFront doesn’t consider headers when caching your objects in edge locations. If your origin returns two objects and they differ only by the values in the request headers, CloudFront caches only one version of the object

Explanation

Application Load Balancer
You are charged for each hour or partial hour that an Application Load Balancer is running and the number of Load Balancer Capacity Units (LCU) used per hour.

Network Load Balancer
You are charged for each hour or partial hour that a Network Load Balancer is running and the number of Load Balancer Capacity Units (LCU) used by Network Load Balancer per hour.

Classic Load Balancer
You are charged for each hour or partial hour that a Classic Load Balancer is running and for each GB of data transferred through your load balancer.

Explanation

A prolonged grace period and a larger number of instances will solve these issues. You can use scaling policies to increase or decrease the number of running EC2 instances in your group automatically to meet changing conditions. When the scaling policy is in effect, the Auto Scaling group adjusts the desired capacity of the group and launches or terminates the instances as needed. If you manually scale or scale on a schedule, you must adjust the desired capacity of the group for the changes to take effect.

Explanation

To host a static website, the user needs to configure an Amazon S3 bucket for website hosting and then upload the website contents to the bucket. The website is then available at the region-specific website endpoint of the bucket.

If the user has an index.html object as part of the bucket, the user can always host it without the website hosting feature. However, it will require an absolute URL of the object. In this case the user can access the whole bucket as a website and need not refer individual objects separately.

Explanation

Amazon SNS and CloudWatch are integrated so you can collect, view, and analyze metrics for every active Amazon SNS notification. By configuring CloudWatch for Amazon SNS, you can gain better insight into the performance of your Amazon SNS topics, push notifications, and SMS deliveries.

Explanation

The user cannot authorize an Amazon EC2 security group if it is in a different AWS Region than the RDS DB instance. The user can authorize an IP range or specify an Amazon EC2 security group in the same region that refers to an IP address in another region. In this case allow IP of US West inside US East’s security group and open the RDS security group for US East region.

Explanation

Most of these choices improve the responsiveness of CloudWatch in some way, but the aspect of this question is improving the responsiveness of CloudWatch alarms you have already implemented. This means you are not interested in additional metric information outside of the custom metrics you’ve already created in CloudWatch, and any features that increase responsiveness to metrics other than what you want will not be beneficial.

So, creating CloudWatch Log metric filters for default RDS metrics will not help, even though this can provide 1-second granularity, it is unlikely the logs will indicate overall latency and throughput of reads and writes, as these performance metrics are not related to specific API calls, but rather general database performance.

Performance Insights allow you to review and analyze your RDS database performance overall, but is not ideal for identifying a performance issue in real-time.

Enabling Enhanced monitoring does provide increased insight into RDS database performance, and with the increased granularity of 5 seconds instead of 60 seconds, or potentially even 1-second granularity through CloudWatch Log Streams. However, Enhanced Monitoring provides specific operating system metrics and other performance metrics, and would not apply to the custom metric you have created using CloudWatch.

Enabling Detailed Monitoring will increase the delivery of average metrics from every 5 minutes to every minute, and this will apply to your custom metrics as well.

In addition, creating a Route 53 CloudWatch Alarm Health Check will monitor the transmission of data to CloudWatch, and can effectively alert you before the CloudWatch alarm is even triggered.

Explanation

Backup and restore, as defined in the “Using Amazon Web Services for Disaster Recovery” white paper, is most like traditional off-site backup replication. You can leverage services such as Amazon S3 or Amazon Storage Gateway to provide a backup replication target and Amazon EC2 can be used to restore access to your applications. This strategy for disaster recovery is the slowest of all AWS DR strategies.

Explanation

You can set up a variety of failover configurations using Amazon Route 53 alias: weighted, latency, geolocation routing, and failover resource record sets. Active-active failover: Use this failover configuration when you want all of your resources to be available the majority of the time. When a resource becomes unavailable, Amazon Route 53 can detect that it’s unhealthy and stop including it when responding to queries. Active-passive failover: Use this failover configuration when you want a primary group of resources to be available the majority of the time and you want a secondary group of resources to be on standby in case all of the primary resources become unavailable. When responding to queries, Amazon Route 53 includes only the healthy primary resources. If allof the primary resources are unhealthy, Amazon Route 53 begins to include only the healthy secondary resources in response to DNS queries. Active-active-passive and other mixed configurations: You can combine alias and non-alias resource record sets to produce a variety of Amazon Route 53 behaviors.

Explanation

Elastic Load Balancing supports both Internet Protocol version 6 (IPv6) and Internet Protocol version 4 (IPv4). Clients can connect to the user’s load balancer using either IPv4 or IPv6 (in EC2-Classic) DNS. However, communication between the load balancer and its back-end instances uses only IPv4. The user can use the Dualstack-prefixed DNS name to enable IPv6 supportfor communications between the client and the load balancers. Thus, the clients are able to access the load balancer using either IPv4 or IPv6 as their individual connectivity needs dictate.

Explanation

A customer gateway CGW is the anchor on the customer side of that connection. It can be a physical or software appliance. The anchor on the AWS side of the VPN connection is called a virtual private gateway VGW. There are two lines between the customer gateway and virtual private gateway because the VPN connection consists of two tunnels in case of device failure. When you configure your customer gateway, it’s important you configure both tunnels.

The VPN connection will connect VGW attached to certain VPC and CGW on AWS.

Public and Private Virtual Interfaces VIFs are part of configuring a Direct Connect between on-premises and AWS

Explanation

By default, a target starts to receive its full share of requests as soon as it is registered with a target group and passes an initial health check. Using slow start mode gives targets time to warm up before the load balancer sends them a full share of requests.

Increasing the maximum threshold for your auto scaling group will allow you to process more requests.

Explanation

EC2 instance store volumes can be added as additional volumes to certain EBS-backed EC2 Instance types. Any data on the instance store volumes persists as long as the instance is running, but this data is deleted when the instance is terminated or if it fails (such as if an underlying drive has issues).