- (Topic 1)
Your entire AWS infrastructure lives inside of one Amazon VPC You have an Infrastructure monitoring application running on an Amazon instance in Availability Zone (AZ) A of the region, and another application instance running in AZ B. The monitoring application needs to make use of ICMP ping to confirm network reachability of the instance hosting the application.
Can you configure the security groups for these instances to only allow the ICMP ping to pass from the monitoring instance to the application instance and nothing else'' If so how?
Correct Answer:D
- (Topic 3)
A sys admin has enabled logging on ELB. Which of the below mentioned fields will not be a part of the log file name?
Correct Answer:B
Elastic Load Balancing access logs capture detailed information for all the requests made to the load balancer. Elastic Load Balancing publishes a log file from each load balancer node at the interval that the user has specified. The load balancer can deliver multiple logs for the same period. Elastic Load Balancing creates log file names in the following format: “{Bucket}/{Prefix}/AWSLogs/{AWS AccountID}/elasticloadbalancing/{Region}/{Year}/{Month}/{Day}/{AWS Account ID}_elasticloadbalancing_{Region}_{Load Balancer Name}_{End Time}_{Load Balancer IP}_{Random String}.log“
- (Topic 3)
A user is trying to send custom metrics to CloudWatch using the PutMetricData APIs. Which of the below
mentioned points should the user needs to take care while sending the data to CloudWatch?
Correct Answer:A
With AWS CloudWatch, the user can publish data points for a metric that share not only the same time stamp, but also the same namespace and dimensions. CloudWatch can accept multiple data points in the same PutMetricData call with the same time stamp. The only thing that the user needs to take care of is that the size of a PutMetricData request is limited to 8KB for HTTP GET requests and 40KB for HTTP POST requests.
- (Topic 1)
You have an Auto Scaling group associated with an Elastic Load Balancer (ELB). You have noticed that instances launched via the Auto Scaling group are being marked unhealthy due to an ELB health check, but these unhealthy instances are not being terminated
What do you need to do to ensure trial instances marked unhealthy by the ELB will be terminated and replaced?
Correct Answer:B
Reference:
http://docs.aws.amazon.com/AutoScaling/latest/DeveloperGuide/as-add-elb-healthcheck.html
Add an Elastic Load Balancing Health Check to your Auto Scaling Group
By default, an Auto Scaling group periodically reviews the results of EC2 instance status to determine the health state of each instance. However, if you have associated your Auto Scaling group with an Elastic Load Balancing load balancer, you can choose to use the Elastic Load Balancing health check. In this case, Auto Scaling determines the health status of your instances by checking the results of both the EC2 instance status check and the Elastic Load Balancing instance health check.
For information about EC2 instance status checks, see.Monitor Instances With Status Checks.in the.Amazon EC2 User Guide for Linux Instances. For information about Elastic Load Balancing health checks, see.Health Check.in the.Elastic Load Balancing Developer Guide.
This topic shows you how to add an Elastic Load Balancing health check to your Auto Scaling group, assuming that you have created a load balancer and have registered the load balancer with your Auto Scaling group. If you have not registered the load balancer with your Auto Scaling group, see.Set Up a Scaled and Load-Balanced Application.
Auto Scaling marks an instance unhealthy if the calls to the Amazon EC2 action.DescribeInstanceStatus.return any state other than.running, the system status shows.impaired, or the calls to Elastic Load Balancing action.DescribeInstanceHealth.returns.OutOfService.in the instance state field.
If there are multiple load balancers associated with your Auto Scaling group, Auto Scaling checks the health state of your EC2 instances by making health check calls to each load balancer. For each call, if the Elastic Load Balancing action returns any state other than.InService, the instance is marked as unhealthy. After Auto Scaling marks an instance as unhealthy, it remains in that state, even if subsequent calls from other load balancers return an.InService.state for the same instance.
- (Topic 2)
A user is planning to setup infrastructure on AWS for the Christmas sales. The user is planning to use Auto Scaling based on the schedule for proactive scaling. What advise would you give to the user?
Correct Answer:C
Auto Scaling based on a schedule allows the user to scale the application in response to predictable load changes. The user can specify any date in the future to scale up or down during that period. As per Auto Scaling the user can schedule an action for up to a month in the future. Thus, it is recommended to wait until end of November before scheduling for Christmas.
- (Topic 3)
A user is measuring the CPU utilization of a private data centre machine every minute. The machine provides the aggregate of data every hour, such as Sum of data”, “Min value”, “Max value, and “Number of Data points”.
The user wants to send these values to CloudWatch. How can the user achieve this?
Correct Answer:C
AWS CloudWatch supports the custom metrics. The user can always capture the custom data and upload the data to CloudWatch using CLI or APIs. The user can publish the data to CloudWatch as single data points or as an aggregated set of data points called a statistic set using the command put-metric-data. When sending the aggregate data, the user needs to send it with the parameter statistic-values: awscloudwatch put-metric-data --metric-name