D.

Canonical user ID

An S3 bucket ACL grantee can be an AWS account or one of the predefined Amazon S3
groups. The user can grant permission to an AWS account by the email address of that
account or by the canonical user ID. If the user provides an email in the grant request,
Amazon S3 finds the canonical user ID for that account and adds it to the ACL. The
resulting ACL will always contain the canonical user ID for the AWS account, and not the
AWS account's email address.

C.

MS SQL

Amazon RDS provides high availability and failover support for DB instances using Multi
AZ deployments. In a Multi AZ deployment, Amazon RDS automatically provisions and
maintains a synchronous standby replica in a different Availability Zone. Multi AZ
deployments for Oracle, PostgreSQL, and MySQL DB instances use Amazon technology,
while SQL Server (MS SQL. DB instances use SQL Server Mirroring.

A.

The snapshot is synchronous

The AWS snapshot is a point in time backup of an EBS volume. When the snapshot
command is executed it will capture the current state of the data that is written on the drive
and take a backup. For a better and consistent snapshot of the root EBS volume, AWS
recommends stopping the instance. For additional volumes it is recommended to unmount
the device. The snapshots are asynchronous and incremental.

C.

Yes, the console will delete all the setups and detach the virtual private gateway

The user can create subnets as per the requirement within a VPC. If the user wants to
connect VPC from his own data centre, he can setup a public and VPN only subnet which
uses hardware VPN access to connect with his data centre. When the user has configured
this setup with Wizard, it will create a virtual private gateway to route all traffic of the VPN
subnet. If the virtual private gateway is attached with VPC and the user deletes the VPC
from the console it will first detach the gateway automatically and only then delete the VPC.

D.

Create another EBS volume in the second Availability Zone attach it to the Amazon EC2
instance, and use a disk manager to mirror me two disks

http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-creating-snapshot.html

B.

By default ELB will select the latest version of the policy

Elastic Load Balancing uses a Secure Socket Layer (SSL. negotiation configuration which is known as a
Security Policy. It is used to negotiate the SSL connections between a client and the load balancer. If the user has created an HTTPS/SSL listener without associating any security policy, Elastic Load Balancing will, bydefault, associate the latest version of the ELBSecurityPolicy-YYYY-MM with the load balancer.

B.

ELB's behavior when sticky sessions are enabled causes ELB to send requests in the
same session to the same backend instance

D.

The web application uses long polling such as comet or websockets. Thereby keeping a
connection open to a web server tor a long time

A.

The private key file has the wrong file permission

While doing SSH to an EC2 instance, if you get an Unprotected Private Key File error it
means that the private key file's permissions on your computer are too open. Ideally the
private key should have the Unix permission of 0400. To fix that, run the command:
chmod 0400 /path/to/private.key