A user has configured Auto Scaling with 3 instances. The user had created a new AMI after updating one of the instances. If the user wants to terminate two specific instances to ensure that Auto Scaling launches an instances with the new launch configuration, which command should he run?
D
The Auto Scaling command as-terminate-instance-in-auto-scaling-group <Instance ID> will terminate the specific instance ID. The user is required to specify the parameter as ג€"no-decrement-desired-capacity to ensure that it launches a new instance from the launch config after terminating the instance. If the user specifies the parameter --decrement-desired-capacity then Auto Scaling will terminate the instance and decrease the desired capacity by 1.
A user has launched an EC2 instance from an instance store backed AMI. If the user restarts the instance, what will happen to the ephemeral storage data?
D
A user can reboot an EC2 instance using the AWS console, the Amazon EC2 CLI or the Amazon EC2 API. Rebooting an instance is equivalent to rebooting an operating system. However, it is recommended that the user use Amazon EC2 to reboot the instance instead of running the operating system reboot command from the instance. When an instance launched from an instance store backed AMI is rebooted all the ephemeral storage data is still preserved.
A user has launched an EC2 instance. However, due to some reason the instance was terminated. If the user wants to find out the reason for termination, where can he find the details?
B
An EC2 instance, once terminated, may be available in the AWS console for a while after termination. The user can find the details about the termination from the description tab under the label State transition reason. If the instance is still running, there will be no reason listed. If the user has explicitly stopped or terminated the instance, the reason will be ג€User initiated shutdownג€.
Reference:
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/Using_InstanceStraightToTerminated.html
A user has created a VPC with CIDR 20.0.0.0/24. The user has used all the IPs of CIDR and wants to increase the size of the VPC. The user has two subnets: public (20.0.0.0/28) and private (20.0.1.0/28). How can the user change the size of the VPC?
B
Once the user has created a VPC, he cannot change the CIDR of that VPC. The user has to terminate all the instances, delete the subnets and then delete the
VPC. Create a new VPC with a higher size and launch instances with the newly created VPC and subnets.
A user has configured ELB with SSL using a security policy for secure negotiation between the client and load balancer. Which of the below mentioned security policies is supported by ELB?
C
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. ELB supports two policies:
Predefined Security Policy, which comes with predefined cipher and SSL protocols;
Custom Security Policy, which allows the user to configure a policy.
A user has granted read/write permission of his S3 bucket using ACL. Which of the below mentioned options is a valid ID to grant permission to other AWS accounts (grantee. using ACL?
D
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.
A user has configured an ELB to distribute the traffic among multiple instances. The user instances are facing some issues due to the back-end servers. Which of the below mentioned CloudWatch metrics helps the user understand the issue with the instances?
D
CloudWatch is used to monitor AWS as well as the custom services. For ELB, CloudWatch provides various metrics including error code by ELB as well as by back-end servers (instances). It gives data for the count of the number of HTTP response codes generated by the back-end instances. This metric does not include any response codes generated by the load balancer. These metrics are:
The 2XX class status codes represents successful actions
The 3XX class status code indicates that the user agent requires action
The 4XX class status code represents client errors
The 5XX class status code represents back-end server errors
A user has launched an EC2 instance store backed instance in the US-East-1a zone. The user created AMI #1 and copied it to the Europe region. After that, the user made a few updates to the application running in the US-East-1a zone. The user makes an AMI#2 after the changes. If the user launches a new instance in
Europe from the AMI #1 copy, which of the below mentioned statements is true?
D
Within EC2, when the user copies an AMI, the new AMI is fully independent of the source AMI; there is no link to the original (source. AMI. The user can modify the source AMI without affecting the new AMI and vice a versa. Therefore, in this case even if the source AMI is modified, the copied AMI of the EU region will not have the changes. Thus, after copy the user needs to copy the new source AMI to the destination region to get those changes.
A user runs the command `dd if=/dev/zero of=/dev/xvdfbs=1M` on a fresh blank EBS volume attached to a Linux instance. Which of the below mentioned activities is the user performing with the command given above?
C
When the user creates a new EBS volume and is trying to access it for the first time it will encounter reduced IOPS due to wiping or initiating of the block storage.
To avoid this as well as achieve the best performance it is required to pre warm the EBS volume. For a blank volume attached with a Linux OS, the ג€ddג€ command is used to write to all the blocks on the device. In the command ג€dd if=/dev/zero of=/dev/xvdfbs=1Mג€ the parameter ג€if =import fileג€ should be set to one of the
Linux virtual devices, such as /dev/zero. The ג€of=output fileג€ parameter should be set to the drive that the user wishes to warm. The ג€bsג€ parameter sets the block size of the write operation; for optimal performance, this should be set to 1 MB.
A user has created an Auto Scaling group using CLI. The user wants to enable CloudWatch detailed monitoring for that group. How can the user configure this?
B
CloudWatch is used to monitor AWS as well as the custom services. It provides either basic or detailed monitoring for the supported AWS products. In basic monitoring, a service sends data points to CloudWatch every five minutes, while in detailed monitoring a service sends data points to CloudWatch every minute.
To enable detailed instance monitoring for a new Auto Scaling group, the user does not need to take any extra steps. When the user creates an Auto Scaling launch config as the first step for creating an Auto Scaling group, each launch configuration contains a flag named InstanceMonitoring.Enabled. The default value of this flag is true. Thus, the user does not need to set this flag if he wants detailed monitoring.
