AWS Certified Solutions Architect Professional – Free Practice Tests

Explanation

The ENI can only be attached to an instance hosted in a VPC. When you move a network interface from one instance to another, network traffic is redirected to the new instance. Some network and security appliances, such as load balancers, network address translation (NAT) servers, and proxy servers prefer to be configured with multiple network interfaces. You can create and attach secondary network interfaces to instances in a VPC that are running these types of applications and configure the additional interfaces with their own public and private IP addresses, security groups, and source/destination checking

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

Blue/green deployments resolve application unavailability during updates.

Explanation

Lifecycle hooks allow customization of existing auto-scaling groups

Explanation

AWS is responsible for the security of the cloud in general, in areas such data security and protection against IP spoofing. The customer is responsible for security in the cloud in areas such as data encryption, installing security patches on EC2 instances, and IAM best practices. It is very important to understand this concept to avoid any lapses in your security measures.

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

The TCO (Total Cost of Ownership) Calculator is used to calculate savings given information about the user’s current environment.

Explanation

If you get an InsufficientInstanceCapacity error when you try to launch an instance or start a stopped instance, AWS does not currently have enough available capacity to service your request. In this situation, reserved instances offer the required reliability to avoid outages and loss of money. Reserved Instances are a long-term capacity reservation, and you will not have to rely on Amazon having enough on-demand capacity. Usually these capacity issues are short term, but due to the nature of the company even short outages can be very costly.

Explanation

Enabling the Multi-AZ option provides high availability and failover support for the replication instance

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

AWS provides an on-demand, scalable infrastructure. Amazon EC2 allows the user to launch On-Demand instances and the organization should create an AMI of the running instance. When the organization is experiencing varying loads and the time of the load is not known but it is higher than the routine traffic it is recommended that the organization launches a few instances beforehand and then setups AutoScaling with policies which scale up and down as per the EC2 metrics, such as Network I/O or CPU utilization.

If the organization keeps all ten additional instances as a part of the AutoScaling policy sometimes during a sudden higher load, it may take time to launch instances and may not give optimal performance. This is the reason it is recommended that the organization keeps an additional five instances running and the next five instances scheduled as per the AutoScaling policy for cost-effectiveness.

Additionally, the website has established a baseline of normal workload outside of the peak season, so they can invest in Standard reserved instances to manage this workload and save dramatically on compute resource costs.

Explanation

The conditions section of a CloudFormation template defines conditions that control whether certain resources are created or whether certain resource properties are assigned a value during stack creation or update. For example, you could conditionally create a resource that depends on whether the stack is for a production or test environment

Explanation

Creating separate VPC Peering connections between each VPC is required for Peering 3 VPCs together. Transitive routing is not supported in VPC Peering so VPC C could not reach VPC A through VPC B. A new VPC Peering connection is required for connecting additional VPCs, so connecting VPC A to pcx-abcxyz is not a viable option. Adding a static route to VPC A that points to pcx-abcxyz would not work as pcx-abcxyz is not connected to VPC A.

Explanation

With AWS IAM a user is creating an application which runs on an EC2 instance and makes requests to AWS, such as DynamoDB or S3 calls. Here it is recommended that the user should not create an IAM user and pass the user's credentials to the application or embed those credentials inside the application. Instead, the user should use roles for EC2 and give that role access to DynamoDB /S3. When the roles are attached to EC2, it will give temporary security credentials to the application hostedon that EC2, to connect with DynamoDB / S3.

Explanation

The technical requirements are file servers running Windows Server 2012 R2 and an Active Directory Schema of at least Server 2008 R2.

Explanation

Amazon API Gateway automatically protects your backend systems from distributed denial-of-service (DDoS) attacks, whether attacked with counterfeit requests (Layer 7) or SYN floods (Layer 3). Additional reading is available here (https://aws.amazon.com/api-gateway/faqs/).

AWS Shield Advanced includes intelligent DDoS attack detection and mitigation for not only for the network layer (layer 3) and transport layer (layer 4) attacks but also for application layer (layer 7) attacks.

NACLs do not provide DDoS mitigation. They are used to control ingress and egress into a subnet based on port and source IP range. Route 53 can protect against DNS based DDoS attacks but does not protect entire layers. Elastic Load Balancing can protect EC2 instances specifically, but not other AWS resources.

Explanation

In certain scenarios, such as when flash traffic is expected, or in the case where a load test cannot be configured to gradually increase traffic, AWS recommends that you have your load balancer "pre-warmed". They will configure the load balancer to have the appropriate level of capacity based on the traffic that you expect. They also need to know the start and end dates of your tests or expected flash traffic, the expected request rate per second and the total size of the typical request/response that you will be testing

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 all of 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

When you resize an instance, you must select an instance type that is compatible with the configuration of the instance. If the instance type that you want is not compatible with the instance configuration you have, then you must migrate your application to a new instance with the instance type that you need. 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 this is the case, you can change the size of your instance. For example, if your t2.micro instance is too small for its workload, you can change it to an m3. medium instance

Explanation

yourwebsite.com is a zone apex. Alias record sets can be used to set a zone apex, but CNAME records cannot. Additionally, queries to Alias records that are mapped to an ELB are free. A records are used to map IPv4 addresses to FQDNs, the IP address of the ELB may change. MX records are used for email servers.

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

To create a NAT gateway, you must specify the public subnet in which the NAT gateway will reside.  You must also specify an Elastic IP address to associate with the NAT gateway when you create it. After you've created a NAT gateway, you must update the route table associated with one or more of your private subnets to point Internet-bound traffic to the NAT gateway. This enables instances in your private subnets to communicate with the Internet.

Each NAT gateway is created in a specific Availability Zone and implemented with redundancy in that zone. You have a limit on the number of NAT gateways you can create in an Availability Zone.

Explanation

The path functionality within an IAM group and user allows them to delineate by further levels. In this case, the user needs to use the path with each user or group so that the ARN of the user will look similar to:

• arn:aws:iam::123456789012:user/division_abc/subdivision_xyz/user1
• arn:aws:iam::123456789012:user/division_abc/subdivision_xyz/user2

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

STS is the “glue” that supports temporary access credentials for federation. If you are running code, AWS CLI, or Tools for Windows PowerShell commands inside an EC2 instance, you can take advantage of roles for Amazon EC2. Otherwise, you can call an AWS STS API to get the temporary credentials, and then use them explicitly to make calls to AWS services.

Explanation

Storage gateways interact with AWS over the public Internet or direct connect. You will need to know the amount of data per day that needs to be transferred to Amazon S3 and the net available bandwidth of your network connection. Storage Gateway is capable of running data compression, and comparison so only changed data is being backed up.

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

Failing to accurately estimate your costs before migration and during the migration process is a recipe for disaster. To build a migration model for optimal efficiency, it is important to accurately understand the current costs of running on-premises applications, as well as the interim costs incurred during the transition

Explanation

Running a DB Instance as a Multi-AZ deployment can further reduce the impact of a maintenance event because Amazon RDS will conduct maintenance by following these steps: Perform maintenance on the standby.

Explanation

Elastic Beanstalk environments can be changed after creation. For example, if you have a compute-intensive application, you can change the type of Amazon EC2 instance that is running your application. To do this, you use the Scaling option in the management page of the Elastic Beanstalk console and change the minimum instance count.

Explanation

Creating a custom AMI of the instance for which you are trying to provide HA allows you to bring the instance online quickly with no build time. Moving the EIP from the instance, you are replacing to the new instance will send all traffic to the new instance without any change to DNS, which would take time to propagate. Using the AutoRecover option will not replace the unhealthy or failing instance. It will only try to restart it on another host. Creating a “Steady State” Auto Scaling Group would also be a good solution, although using two as a minimum would have a higher cost.

Explanation

In Elastic Beanstalk, you can create a load-balancing, autoscaling environment or a single-instance environment. The type of environment that you require depends on the application that you deploy. For example, you can develop and test an application in a single-instance environment to save costs and then upgrade that environment to a load-balancing, autoscaling environment when the application is ready for production.

Explanation

Amazon S3 is storage for the Internet. It's a simple storage service that offers software developers a highly-scalable, reliable, and low-latency data storage infrastructure at very low costs. AWS charges less where their costs are less. For example, their costs are lower in the US Standard Region than in the US West (Northern California) Region.

Explanation

Amazon CloudWatch integrates with AWS Identity and Access Management (IAM) so that you can specify which CloudWatch actions a user in your AWS Account can perform. For example, you could create an IAM policy that gives only certain users in your organization permission to use GetMetricStatistics. They could then use the action to retrieve data about your cloud resources. You can't use IAM to control access to CloudWatch data for specific resources. For example, you can't give a user accessto CloudWatch data for only a specific set of instances or a specific LoadBalancer. Permissions granted using IAM coverall the cloud resources you use with CloudWatch. In addition, you can't use IAM roles with the Amazon CloudWatch command line tools. Using Amazon CloudWatch with IAM doesn't change how you use CloudWatch. There are no changes to CloudWatch actions, and no new CloudWatch actions related to users and access control.

Explanation

STS is the “glue” that supports temporary access credentials for federation. If you are running code, AWS CLI, or Tools for Windows PowerShell commands inside an EC2 instance, you can take advantage of roles for Amazon EC2. Otherwise, you can call an AWS STS API to get the temporary credentials, and then use them explicitly to make calls to AWS services.

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

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

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

Lifecycle hooks allow customization of existing auto-scaling groups

Explanation

Amazon Elastic Compute Cloud (Amazon EC2) provides scalable computing capacity in the Amazon Web Services (AWS) cloud. Using Amazon EC2 eliminates your need to invest in hardware up front, so you can develop and deploy applications faster. You can use Amazon EC2 to launch as many or as few virtual servers as you need, configure security and networking, and manage storage. Amazon EC2 enables you to scale up or down to handle changes in requirements or spikes in popularity, reducing your need to forecast traffic

Explanation

An elastic network interface is a virtual network interface that you can attach to an instance in a VPC. Network interfaces are available only for instances running in a VPC.  If one of your instances serving a particular function fails, its network interface can be attached to a replacement or hot standby instance pre-configured for the same role to rapidly recover the service.

Explanation

Versioning provides redundancy as it keeps multiple variants of an object in the same bucket. You can use versioning to preserve, retrieve, and restore every version of every object stored in your Amazon S3 bucket. With versioning, you can easily recover from both unintended user actions and application failures.

Explanation

You can create a VPC with an instance tenancy of dedicated to ensure that all instances launched into the VPC are dedicated instances. Alternatively, you can specify the tenancy of the instance during launch

Explanation

Amazon S3 stores objects according to their storage class. There are technically four major storage classes: Standard, Standard - Infrequent Access, Reduced Redundancy Storage (RRS) and Glacier.

Standard is for Amazon S3 and provides very high durability. Standard - Infrequent Access is designed for with a minimum data amount required and paid storage for at least 30 days. Glacier is for archival and the files are not available over the internet. Reduced Redundancy Storage is for less critical files.

S3 OneZone IA is a variation of Standard-IA, which offers data archival at a reduced price, but also with less durability because the data within this class is stored within a single availability zone rather than spread throughout all availability zones within the S3 buckets region, as it is with S3 Standard storage.

Explanation

The technical requirements are file servers running Windows Server 2012 R2 and an Active Directory Schema of at least Server 2008 R2.

Explanation

Several factors can affect the performance of Amazon EBS volumes, such as instance configuration, I/O characteristics, workload demand, and storage configuration. IOPS are input/output operations per second. Amazon EBS measures each I/O operation per second (that is 256 KB or smaller) as one IOPS. I/O operations that are larger than 256 KB are counted in 256 KB capacity units. For example, a 1,024 KB I/O operation would count as 4 IOPS. When you provision a 4,000 IOPS volume and attach it to an EBS-optimized instance that can provide the necessary bandwidth, you can transfer up to 4,000 chunks of data per second (provided that the I/O does not exceed the 128 MB/s per volume throughput limit of General Purpose (SSD) and Provisioned IOPS (SSD) volumes).

Explanation

You restrict access to Amazon S3 content by creating an origin access identity, which is a special CloudFront user. You change Amazon S3 permissions to give the origin access identity permission to access your objects, and to remove permissions from everyone else. When your users access your Amazon S3 objects using CloudFront URLs, the CloudFront origin access identity gets the objects on your users' behalf. If your users try to access objects using Amazon S3 URLs, they're denied access. The origin access identity has permission to access objects in your Amazon S3 bucket, but users don't.

Explanation

The conditions section of a CloudFormation template defines conditions that control whether certain resources are created or whether certain resource properties are assigned a value during stack creation or update. For example, you could conditionally create a resource that depends on whether the stack is for a production or test environment

Explanation

Recovery takes IOPS; therefore, insufficient IOPS will slow down failover time. Database recovery relies on transactions; therefore, smaller transactions will shorten failover time.

Explanation

The TCO (Total Cost of Ownership) Calculator is used to calculate savings given information about the user’s current environment.

Explanation

Each Amazon S3 bucket and object has an ACL (Access Control List) associated with it. An ACL is a list of grants identifying the grantee and the permission granted. The user can use ACLs to grant basic read/write permissions to other AWS accounts. ACLs use an Amazon S3–specific XML schema. The user cannot grant permissions to other users in his account. ACLs are suitable for specific scenarios. For example, if a bucket owner allows other AWS accounts to upload objects, permissions to these objects can only be managed using the object ACL by the AWS account that owns the object

Explanation

SQS allows you to quickly build hosted and scalable message queuing applications that can run on any computer. SQS stores messages in transit between diverse, distributed application components without losing messages and without requiring each component to be always available

Explanation

Quick Start is a new solution that is worth checking out. You can use IAM with AWS CloudFormation to control what users can do with AWS CloudFormation. Amazon provides Amazon Linux AMIs that are configured to run as NAT instances. Elastic Beanstalk is primarily for web applications only

Explanation

Both instance status checks and health checks must be enabled before unhealthy instances will be terminated. It is critical that you test not only the saturation and breaking points but also the "normal" traffic profile you expect

Explanation

The Simple Monthly Calculator is used to calculate projected costs, assuming you know what AWS resources you’ll be consuming.

Explanation

You can reduce EC2 spend by migrating to reserved/spot instances, eliminating/shrinking unused resources, or consolidating AWS accounts (to qualify for volume discounts). The paying account's use of consolidated billing can benefit from volume pricing discounts gained thru aggregate account usage.

Explanation

The Warm Standby scenario uses a scaled-down version of a fully functional environment that is always running. Business-critical applications can always be running in the cloud. When a DR scenario comes about, the servers can be quickly scaled up, scaled out or both, but horizontal scaling is preferred over vertical scaling.

The two incorrect choices will increase your environment's resilience by adding availability

Explanation

The path functionality within an IAM group and user allows them to delineate by further levels. In this case, the user needs to use the path with each user or group so that the ARN of the user will look similar to:

• arn:aws:iam::123456789012:user/division_abc/subdivision_xyz/user1
• arn:aws:iam::123456789012:user/division_abc/subdivision_xyz/user2

Explanation

AWS Identity and Access Management is a web service that allows organizations to manage users and user permissions for various AWS services. The user can add conditions as a part of the IAM policies. The condition can be set on AWS Tags, Time, and Client IP as well as on various parameters. If the organization wants the user to access only specific instances, he should define proper tags and add to the IAM policy condition. The sample policy is shown below.
 "Statement": [
{
"Action": "ec2:*",
"Effect": "Allow",
"Resource": "*",
"Condition": {
"StringEquals": {
"ec2:ResourceTag/InstanceType": "Production"
}
}
}
]

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

You can run Amazon RDS for Oracle under two different licensing models – “License Included” and “Bring-Your-Own-License (BYOL)”. In the "License Included" service model, you do not need separately purchased Oracle licenses; the Oracle Database software has been licensed by AWS.

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

When you resize an instance, you must select an instance type that is compatible with the configuration of the instance. If the instance type that you want is not compatible with the instance configuration you have, then you must migrate your application to a new instance with the instance type that you need. 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 this is the case, you can change the size of your instance. For example, if your t2.micro instance is too small for its workload, you can change it to an m3. medium instance

Explanation

To configure a bucket for static website hosting, you add a website configuration to your bucket. The configuration includes an index document, error documents, redirects of all requests that are intended for the index page, and any conditional redirects. Amazon S3 does not support server-side scripting.

Explanation

Public and private subnets, except for the default VPC, do not automatically have Internet access enabled. To enable access to or from the Internet for instances in a VPC subnet, you must do the following:

Explanation

Explanation

The organization can always launch multiple EC2 instances in the same region across multiple availability zones for high availability and disaster recovery. It is recommended that the application should be load balanced for better load distribution. When the organization must support a workload that could be met with a small number of large instances, it is recommended to distribute the load by creating four small instances across availability zones. The two large instances give only 50% redundancy while the four small instances give 75% redundancy. As for cost, both the scenarios are the same it is recommended to run four small instances across availability zones

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

The AWS Storage Gateway is a service connecting an on-premises software appliance with cloud-based storage to provide seamless and secure integration between an organization's on-premises IT environment and AWS's storage infrastructure. AWS Storage Gateway billing is as follows. Volume storage usage (per GB per month): You are billed for the Cached volume data you store in Amazon S3. You are only billed for volume capacity you use, not for the size of the volume you create. Snapshot Storage usage (per GB per month): You are billed for the snapshots your gateway stores in Amazon S3. These snapshots are stored and billed as Amazon EBS snapshots. Snapshots are incremental backups, reducing your storage charges. When taking a new snapshot, only the data that has changed since your last snapshot is stored. Virtual Tape Library usage (per GB per month): You are billed for the virtual tape data you store in Amazon S3. You are only billed for the portion of virtual tape capacity that you use, not for the size of the virtual tape. Virtual Tape Shelf usage (per GB per month): You are billed for the virtual tape data you store in Amazon Glacier. You are only billed for the portion of virtual tape capacity that you use, not for the size of the virtual tape

Explanation

AWS Storage Gateway enables applications that are clustered using Windows Server Failover Clustering (WSFC) to use the iSCSI initiator to access a gateway's volumes. However, connecting multiple hosts to the same iSCSI target is not supported. When using Red Hat Enterprise Linux (RHEL), you use the iscsi-initiator-utils RPM package to connect to your gateway iSCSI targets (volumes or VTL devices).

Explanation

Uploading data to the Snowball Appliance requires a client application. The upload is CPU, memory, and networking intensive. If you are uploading large amounts of data, Amazon recommends that you run the client software on multiple workstations to distribute the load and thereby shorten the time the upload will take.

Explanation

Amazon API Gateway automatically protects your backend systems from distributed denial-of-service (DDoS) attacks, whether attacked with counterfeit requests (Layer 7) or SYN floods (Layer 3). Additional reading is available here (https://aws.amazon.com/api-gateway/faqs/).

AWS Shield Advanced includes intelligent DDoS attack detection and mitigation for not only for the network layer (layer 3) and transport layer (layer 4) attacks but also for application layer (layer 7) attacks.

NACLs do not provide DDoS mitigation. They are used to control ingress and egress into a subnet based on port and source IP range. Route 53 can protect against DNS based DDoS attacks but does not protect entire layers. Elastic Load Balancing can protect EC2 instances specifically, but not other AWS resources.

Explanation

To enable SAML-Based federation for AWS Account, the following actions are required

1- Inside your organization's network, you configure your identity store (such as Windows Active Directory) to work with a SAML-based identity provider (IdP) like Windows Active Directory Federation Services

2- In IAM, create a new SAML provider, which is an entity in IAM that holds information about your organization's identity provider.

3- You also need to create roles that will map to allowed groups in company's identity store, members of these groups will be presented with set of roles that map to their group membership to choose which role they would like to assume while logging in to AWS console

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

AWS will choose the most specific route first. If routes are equal after checking for the most specific routes, AWS will use AS path prepending to determine which route is preferred. In this example, 10.20.30.0/25 is more specific than 10.20.30.0/24 and 10.20.0.0/16, so AS path prepending will not matter. The other options are either outside of the address range in question (10.20.30.128/26 and 10.20.128.0/17) or less specific than the route advertised by Houston (10.20.30.0/23). The route advertised from Orlando, 10.20.30.254/32, identifies a single IPv4 address that is outside of the range in question

Explanation

A Virtual Private Cloud (VPC) is a virtual network dedicated to the user’s AWS account. It enables the user to launch AWS resources into a virtual network that the user has defined. An Elastic Network Interface (ENI) is a virtual network interface that the user can attach to an instance in a VPC.

The ENI allows the user to change the security group of a running instance. Thus, in the present scenario when the organization wants to have a separate security group for one of the instances, it should change the security group of that ENI. This avoids the cost and time of deploying a new instance or configuring a new subnet, or changing the configuration of an existing security group.

Explanation

DynamoDB supports two types of secondary indexes: Local secondary index --an index that has the same hash key as the table, but a different range key. A local secondary index is "local" in the sense that every partition of a local secondary index is scoped to a table partition that has the same hash key. Global secondary index --an index with a hash and range key that can be different from those on the table. A global secondary index is considered "global" because queries on the index can span all of the data in a table, across all partitions

Explanation

With AWS CloudTrail, you can get a history of AWS API calls for your account, including API calls made via the AWS Management Console, the AWS SDKs, the command line tools, and higher-level AWS services. You can also identify which users and accounts called AWS APIs for services that support CloudTrail, the source IP address the calls were made from, and when the calls occurred. You can identify which users and accounts called AWS for services that support CloudTrail, the source IP address the calls were made from, and when the calls occurred. You can integrate CloudTrail into applications using the API, automate trail creation for your organization, check the status of your trails, and control how administrators turn CloudTrail logging on and off.

Explanation

To establish a baseline you should, at a minimum, monitor the following items:

• CPU Utilization
• Memory Utilization
• Network Utilization
• Disk Performance
• Disk Space.

Explanation

When scaling an RDS instance, changes can be applied immediately or during the maintenance window specified. It is also recommended that you before you scale, make sure you have the correct licensing in place for commercial engines (SQL Server, Oracle) especially if you Bring Your Own License (BYOL). One important thing to call out is that for commercial engines, you are restricted by the license, which is usually tied to the CPU sockets or cores.

Explanation

Read replicas of your master database allow you to increase performance. Placing your read replicas in different AWS regions closer to your users will maximize performance and increase the availability of your database.

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

After you turn on S3 Transfer Acceleration for a bucket, two new endpoints are created for the bucket: one for IPv4 and one for IPv6. You can use either the accelerate endpoints or the standard endpoints if you choose not to use the accelerate feature.

Explanation

Both Snowball and VM Import can be used to migrate VMs. Snowball mitigates any bandwidth issues that may occur when using VM Import with standard Internet connections.

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

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

Many instances can poll a single queue, but to keep multiple instances from processing the same SQS message, your application must delete the SQS message after processing it. While SQS does not guarantee a message will be processed only once, the same message being processed many times is probably an indication that the message is not being deleted following processing.

Explanation

You can secure your VPC instances using only security groups; however, you can add NACLs as a second layer of defense. 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 (NACLs) — Act as a firewall for associated subnets, controlling both inbound and outbound traffic at the subnet level . Security Groups supports allow rules only while Network Access Control Lists support allow and deny rules.

Explanation

Turning off automatic backups or logging on the target database during the migration will help increase the speed of the initial migration load.

Explanation

In AWS, the instance size decides the I/O characteristics. The provisioned IOPS ensures higher throughput, and lower latency. The region does affect the latency, latency will always be less when the instance is near to the end user. Within a region the user uses any AZ and this does not affect the latency. The AZ is mainly for fault toleration or HA

Explanation

If you get an InsufficientInstanceCapacity error when you try to launch an instance or start a stopped instance, AWS does not currently have enough available capacity to service your request. In this situation, reserved instances offer the required reliability to avoid outages and loss of money. Reserved Instances are a long-term capacity reservation, and you will not have to rely on Amazon having enough on-demand capacity. Usually these capacity issues are short term, but due to the nature of the company even short outages can be very costly.

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

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

Creating separate VPC Peering connections between each VPC is required for Peering 3 VPCs together. Transitive routing is not supported in VPC Peering so VPC C could not reach VPC A through VPC B. A new VPC Peering connection is required for connecting additional VPCs, so connecting VPC A to pcx-abcxyz is not a viable option. Adding a static route to VPC A that points to pcx-abcxyz would not work as pcx-abcxyz is not connected to VPC A.