Amazon (SAP-C01) Exam Questions And Answers page 75

Amazon Machine Images that use paravirtual (PV) virtualization use a system called PV-GRUB during the boot process. PV-GRUB is a paravirtual boot loader that runs a patched version of GNU GRUB 0.97. When you start an instance, PV-GRUB starts the boot process and then chain loads the kernel specified by your image's menu.lst file.

In Amazon Web Services, to help manage EC2 instances as well their usage in a better way, the user can tag the instances. The tags are metadata assigned by the user which consists of a key and value. The tag key cannot have a prefix as "aws:", although it can have only "aws".

While implementing the policy keys in Amazon RDS, if you use aws: SourceIp and the request comes from an Amazon EC2 instance, the instance's public IP address is evaluated to determine if access is allowed.

You are in charge of configuring the routing tables of your VPC as well as the network ACLs rules needed to make your DB instances accessible from all the instances of your VPC that need to communicate with it.

No, snapshots are only available through the Amazon EC2 APIs.

AWS EC2 Spot Instances allow the user to quote his own price for the EC2 computing capacity. The user can simply bid on the spare Amazon EC2 instances and run them whenever his bid exceeds the current Spot Price. The Spot Instance pricing model complements the On-Demand and Reserved Instance pricing models, providing potentially the most cost-effective option for obtaining compute capacity, depending on the application. The only challenge with a Spot Instance is data persistence as the instance can be terminated whenever the spot price exceeds the bid price. In the current scenario a Hadoop job is a temporary job and does not run for a longer period. It fetches data from a persistent DynamoDB. Thus, even if the instance gets terminated there will be no data loss and the job can be re-run. As the output files are large temporary files, it will be useful to store data on ethereal storage for cost savings.

Within an IAM policy, IfExists can be added to the end of any condition operator except the Null condition. It can be used to indicate that conditional comparison needs to happen if the policy key is present in the context of a request; otherwise, it can be ignored.

Use groups to assign permissions to IAM users
Instead of defining permissions for individual IAM users, it s usually more convenient to create groups that relate to job functions (administrators, developers, accounting, etc.), define the relevant permissions for each group, and then assign IAM users to those groups. All the users in an IAM group inherit the permissions assigned to the group. That way, you can make changes for everyone in a group in just one place. As people move around in your company, you can simply change what IAM group their IAM user belongs to.

Regardless of how your Lambda function is invoked, AWS Lambda always executes the function. At the time you create a Lambda function, you specify an IAM role that AWS Lambda can assume to execute your Lambda function on your behalf. This role is also referred to as the execution role.