AWS SysOps Study List - CloudWatch

CLOUDWATCH

Basics

• Monitoring tool for AWS services
• Basic monitoring in 5 minute intervals, detailed in 1 minute
• User data can be inputted through API
• PutMetricData API
• Statistics
• "Sum of data","Min value”, “Max value, and “Number of Data points”.
• Each PutMetricData request is limited to 8 KB in size for HTTP GET requests and is limited to 40 KB in size for HTTP POST requests.
• Data collecting from several +1 regions need to enabled and then aggregated
• Endpoint URL monitoring.us-east-1.amazonaws.com
• Accepts future data
• Use zero (0) for empty data

Limits

• Does not monitor memory usage, requires custom metric

Following topics are exam questions collected through Internet and should be evaluated as so. Answers are mine and have been checked with answers collected through the internet, but might still be wrong.

A user is having data generated randomly based on a certain event. The user wants to upload that data to CloudWatch. It may happen that event may not have data generated for some period due to andomness. Which of the below mentioned options is a recommended option for this case?

A. For the period when there is no data, the user should not send the data at all
B. For the period when there is no data the user should send a blank value
C. For the period when there is no data the user should send the value as 0
D. The user must upload the data to CloudWatch as having no data for some period will cause an error at CloudWatch monitoring

You are creating an Auto Scaling group whose instances need to insert a custom metric into CloudWatch. Which method would be the best way to authenticate your CloudWatch PUT request?

A. Create an IAM role with the Put Metric Data permission and modify the Auto Scaling launch configuration to launch instances in that role
B. Create an IAM user with the Put Metric Data permission and modify the Auto Scaling launch configuration to inject the users credentials into the instance User Data
C. Modify the appropriate CloudWatch metric policies to allow the Put Metric Data permission to instances from the Auto Scaling group
D. Create an IAM user with the Put Metric Data permission and put the credentials in a private repository and have applications on the server pull the credentials as needed

Why? Ruling out B and D for using IAM user. From A and C, role version sounds better as IAM roles should be used whenever possible



You have set up Individual AWS accounts for each project. You have been asked to make sure your AWS Infrastructure costs do not exceed the budget set per project for each month. Which of the following approaches can help ensure that you do not exceed the budget each month?

A. Consolidate your accounts so you have a single bill for all accounts and projects
B. Set up auto scaling with CloudWatch alarms using SNS to notify you when you are running too many Instances in a given account
C. Set up CloudWatch billing alerts for all AWS resources used by each project, with a notification occurring when the amount for each resource tagged to a particular project matches the budget allocated to the project
D. Set up CloudWatch billing alerts for all AWS resources used by each account, with email notifications when it hits 50%, 80% and 90% of its budgeted monthly spend

Why? A and B can be ruled out rightaway. C can be ruled out as it's discussing individual resources, hence D.


Your EC2-Based Multi-tier application includes a monitoring instance that periodically makes application -level read only requests of various application components and if any of those fail more than three times 30 seconds calls CloudWatch to fire an alarm, and the alarm notifies your operations team by email and SMS of a possible application health problem. However, you also need to watch the watcher-the monitoring instance itself-and be notified if it becomes unhealthy. Which of the following is a simple way to achieve that goal?

A. Run another monitoring instance that pings the monitoring instance and fires a CloudWatch alarm mat notifies your operations team should the primary monitoring instance become unhealthy.
B. Set a CloudWatch alarm based on EC2 system and instance status checks and have the alarm notify your operations team of any detected problem with the monitoring instance.
C. Set a CloudWatch alarm based on the CPU utilization of the monitoring instance and have the alarm notifies your operations team if the CPU usage exceeds 50% few more than one minute: then have your monitoring application go into a CPU-bound loop should it Detect any application problems.
D. Have the monitoring instances post messages to an SQS queue and then dequeuer those messages on another instance should DC-the queue cease to have new messages, the second instance should first terminate the original monitoring instance start another backup monitoring instance and assume the role of the previous monitoring instance and beginning adding messages to the SQS queue.

Why? B is the most easiest and flexible way of implementing monitoring on this case.


An application that you are managing has EC2 instances & DynamoDB tables deployed to several AWS Regions. In order to monitor the performance of the application globally, you would like to see two graphs 1) Avg CPU Utilization across all EC2 instances and 2) Number of Throttled Requests for all DynamoDB tables. How can you accomplish this?

A. Tag your resources with the application name, and select the tag name as the dimension in the CloudWatch Management console to view the respective graphs
B. Use the CloudWatch CLI tools to pull the respective metrics from each regional endpoint. Aggregate the data offline & store it for graphing in CloudWatch.
C. Add SNMP traps to each instance and DynamoDB table. Leverage a central monitoring server to capture data from each instance and table. Put the aggregate data into CloudWatch for graphing.
D. Add a CloudWatch agent to each instance and attach one to each DynamoDB table. When configuring the agent set the appropriate application name & view the graphs in CloudWatch.

Why? http://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/GetSingleMetricAllDimensions.html "You can aggregate the metrics for AWS resources across multiple resources. Note that Amazon CloudWatch cannot aggregate data across regions. Metrics are completely separate between regions." which means that you need to use CloudWatch CLI tools to pull the data and aggregate the data offline.


Which of the following requires a custom CloudWatch metric to monitor?

A. Data transfer of an EC2 instance
B. Disk usage activity of an EC2 instance
C. Memory Utilization of an EC2 instance
D. CPU Utilization of an EC2 instance


A user has setup a CloudWatch alarm on an EC2 action when the CPU utilization is above 75%. The alarm sends a notification to SNS on the alarm state. If the user wants to simulate the alarm action how can he achieve this?

A. Run activities on the CPU such that its utilization reaches above 75%
B. From the AWS console change the state to ‘Alarm’
C. The user can set the alarm state to ‘Alarm’ using CLI
D. Run the SNS action manually


A user has setup a billing alarm using CloudWatch for $200. The usage of AWS exceeded $200 after some days. The user wants to increase the limit from $200 to $400? What should the user do?

A. Create a new alarm of $400 and link it with the first alarm
B. It is not possible to modify the alarm once it has crossed the usage limit
C. Update the alarm to set the limit at $400 instead of $200
D. Create a new alarm for the additional $200 amount


A user is trying to aggregate all the CloudWatch metric data of the last 1 week. Which of the below mentioned statistics is not available for the user as a part of data aggregation?

A. Aggregate
B. Sum
C. Sample data
D. Average


A user has a refrigerator plant. The user is measuring the temperature of the plant every 15 minutes. If the user wants to send the data to CloudWatch to view the data visually, which of the below mentioned statements is true with respect to the information given above?

A. The user needs to use AWS CLI or API to upload the data
B. The user can use the AWS Import Export facility to import data to CloudWatch
C. The user will upload data from the AWS console
D. The user cannot upload data to CloudWatch since it is not an AWS service metric


An organization has configured the custom metric upload with CloudWatch. The organization has given permission to its employees to upload data using CLI as well SDK. How can the user track the calls made to CloudWatch?

A. The user can enable logging with CloudWatch which logs all the activities
B. Use CloudTrail to monitor the API calls
C. Create an IAM user and allow each user to log the data using the S3 bucket
D. Enable detailed monitoring with CloudWatch


A user is publishing custom metrics to CloudWatch. Which of the below mentioned statements will help the user understand the functionality better?

A. The user can use the CloudWatch Import tool
B. The user should be able to see the data in the console after around 15 minutes
C. If the user is uploading the custom data, the user must supply the namespace, timezone, and metric name as part of the command
D. The user can view as well as upload data using the console, CLI and APIs


A user has configured an Auto Scaling group with ELB. The user has enabled detailed CloudWatch monitoring on Elastic Load balancing. Which of the below mentioned statements will help the user understand this functionality better?

A. ELB sends data to CloudWatch every minute only and does not charge the user
B. ELB will send data every minute and will charge the user extra
C. ELB is not supported by CloudWatch
D. It is not possible to setup detailed monitoring for ELB


A user has setup Auto Scaling with ELB on the EC2 instances. The user wants to configure that whenever the CPU utilization is below 10%, Auto Scaling should remove one instance. How can the user configure this?

A. The user can get an email using SNS when the CPU utilization is less than 10%. The user can use the desired capacity of Auto Scaling to remove the instance
B. Use CloudWatch to monitor the data and Auto Scaling to remove the instances using scheduled actions
C. Configure CloudWatch to send a notification to Auto Scaling Launch configuration when the CPU utilization is less than 10% and configure the Auto Scaling policy to remove the instance
D. Configure CloudWatch to send a notification to the Auto Scaling group when the CPU Utilization is less than 10% and configure the Auto Scaling policy to remove the instance


A user has enabled detailed CloudWatch metric monitoring on an Auto Scaling group. Which of the below mentioned metrics will help the user identify the total number of instances in an Auto Scaling group cluding pending, terminating and running instances?

A. GroupTotalInstances
B. GroupSumInstances
C. It is not possible to get a count of all the three metrics together. The user has to find the individual number of running, terminating and pending instances and sum it
D. GroupInstancesCount


A user is trying to configure the CloudWatch billing alarm. Which of the below mentioned steps should be performed by the user for the first time alarm creation in the AWS Account Management section?

A. Enable Receiving Billing Reports
B. Enable Receiving Billing Alerts
C. Enable AWS billing utility
D. Enable CloudWatch Billing Threshold


A user is checking the CloudWatch metrics from the AWS console. The user notices that the CloudWatch data is coming in UTC. The user wants to convert the data to a local time zone. How can the user perform this?

A. In the CloudWatch dashboard the user should set the local timezone so that CloudWatch shows the data only in the local time zone
B. In the CloudWatch console select the local timezone under the Time Range tab to view the data as per the local timezone
C. The CloudWatch data is always in UTC; the user has to manually convert the data
D. The user should have send the local timezone while uploading the data so that CloudWatch will show the data only in the local timezone


A user has configured CloudWatch monitoring on an EBS backed EC2 instance. If the user has not attached any additional device, which of the below mentioned metrics will always show a 0 value?

A. DiskReadBytes
B. NetworkIn
C. NetworkOut
D. CPUUtilization


A user wants to make so that whenever the CPU utilization of the AWS EC2 instance is above 90%, the redlight of his bedroom turns on. Which of the below mentioned AWS services is helpful for this purpose?

A. AWS CloudWatch + AWS SES
B. AWS CloudWatch + AWS SNS
C. None. It is not possible to configure the light with the AWS infrastructure services
D. AWS CloudWatch and a dedicated software turning on the light


A user has setup an EBS backed instance and a CloudWatch alarm when the CPU utilization is more than 65%. The user has setup the alarm to watch it for 5 periods of 5 minutes each. The CPU utilization is 60% between 9 AM to 6 PM. The user has stopped the EC2 instance for 15 minutes between 11 AM to 11:15 AM. What will be the status of the alarm at 11:30 AM?

A. Alarm
B. OK
C. Insufficient Data
D. Error


A user has setup a web application on EC2. The user is generating a log of the application performance at every second. There are multiple entries for each second. If the user wants to send that data to CloudWatch every minute, what should he do?

A. The user should send only the data of the 60th second as CloudWatch will map the receive data timezone with the sent data timezone
B. It is not possible to send the custom metric to CloudWatch every minute
C. Give CloudWatch the Min, Max, Sum, and SampleCount of a number of every minute
D. Calculate the average of one minute and send the data to CloudWatch


A user is displaying the CPU utilization, and Network in and Network out CloudWatch metrics data of a single instance on the same graph. The graph uses one Y-axis for CPU utilization and Network in and another Y-axis for Network out. Since Network in is too high, the CPU utilization data is not visible clearly on graph to the user. How can the data be viewed better on the same graph?

A. It is not possible to show multiple metrics with the different units on the same graph
B. Add a third Y-axis with the console to show all the data in proportion
C. Change the axis of Network by using the Switch command from the graph
D. Change the units of CPU utilization so it can be shown in proportion with Network

Why? http://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/switch_graph_axes.html "You can set custom bounds for the Y axis on a graph to help you see the data better. For example, you can change the bounds on a CPUUtilization graph to 100 percent so that it's easy to see whether the CPU is low (the plotted line is near the bottom of the graph) or high (the plotted line is near the top of the graph). You can switch between two different Y axes for your graph. This is particularly useful if the graph contains metrics that have different units or that differ greatly in their range of values."


A user has setup an EBS backed instance and attached 2 EBS volumes to it. The user has setup a CloudWatch alarm on each volume for the disk data. The user has stopped the EC2 instance and detached the EBS volumes. What will be the status of the alarms on the EBS volume?

A. OK
B. Insufficient Data
C. Alarm
D. The EBS cannot be detached until all the alarms are removed


An organization is measuring the latency of an application every minute and storing data inside a file in the JSON format. The organization wants to send all latency data to AWS CloudWatch. How can the organization achieve this?

A. The user has to parse the file before uploading data to CloudWatch
B. It is not possible to upload the custom data to CloudWatch
C. The user can supply the file as an input to the CloudWatch command
D. The user can use the CloudWatch Import command to import data from the file to CloudWatch


A user is using the AWS EC2. The user wants to make so that when there is an issue in the EC2 server, such as instance status failed, it should start a new instance in the user’s private cloud. Which AWS service helps to achieve this automation?

A. AWS CloudWatch + Cloudformation
B. AWS CloudWatch + AWS AutoScaling + AWS ELB
C. AWS CloudWatch + AWS VPC
D. AWS CloudWatch + AWS SNS

Why? http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-recover.html


A user is observing the EC2 CPU utilization metric on CloudWatch. The user has observed some interesting patterns while filtering over the 1 week period for a particular hour. The user wants to zoom that data point to a more granular period. How can the user do that easily with CloudWatch?

A. The user can zoom a particular period by selecting that period with the mouse and then releasing the mouse
B. The user can zoom a particular period by double clicking on that period with the mouse
C. The user can zoom a particular period by specifying the aggregation data for that period
D. The user can zoom a particular period by specifying the period in the Time Range


A user has created an Auto Scaling group with default configurations from CLI. The user wants to setup the CloudWatch alarm on the EC2 instances, which are launched by the Auto Scaling group. The user has setup an alarm to monitor the CPU utilization every minute. Which of the below mentioned statements is true?

A. It will fetch the data at every minute but the four data points [corresponding to 4 minutes] will not have value since the EC2 basic monitoring metrics are collected every five minutes
B. It will fetch the data at every minute as detailed monitoring on EC2 will be enabled by the default launch configuration of Auto Scaling
C. The alarm creation will fail since the user has not enabled detailed monitoring on the EC2 instances
D. The user has to first enable detailed monitoring on the EC2 instances to support alarm monitoring at every minute


A user is configuring a CloudWatch alarm on RDS to receive a notification when the CPU utilization of RDS is higher than 50%. The user has setup an alarm when there is some inactivity on RDS, such as RDS unavailability. How can the user configure this?

A. Setup the notification when the CPU is more than 75% on RDS
B. Setup the notification when the state is Insufficient Data
C. Setup the notification when the CPU utilization is less than 10%
D. It is not possible to setup the alarm on RDS


A user had aggregated the CloudWatch metric data on the AMI ID. The user observed some abnormal behaviour of the CPU utilization metric while viewing the last 2 weeks of data. The user wants to share that data with his manager. How can the user achieve this easily with the AWS console?

A. The user can use the copy URL functionality of CloudWatch to share the exact details
B. The user can use the export data option from the CloudWatch console to export the current data point
C. The user has to find the period and data and provide all the aggregation information to the manager
D. The user can use the CloudWatch data copy functionality to copy the current data points


A user has setup a CloudWatch alarm on the EC2 instance for CPU utilization. The user has setup to receive a notification on email when the CPU utilization is higher than 60%. The user is running a virus scan on the same instance at a particular time. The user wants to avoid receiving an email at this time. What should the user do?

A. Remove the alarm
B. Disable the alarm for a while using CLI
C. Modify the CPU utilization by removing the email alert
D. Disable the alarm for a while using the console


A user has setup a custom application which generates a number in decimals. The user wants to track that number and setup the alarm whenever the number is above a certain limit. The application is sending the data to CloudWatch at regular intervals for this purpose. Which of the below mentioned statements is not true with respect to the above scenario?

A. The user can get the aggregate data of the numbers generated over a minute and send it to
CloudWatch
B. The user has to supply the timezone with each data point
C. CloudWatch will not truncate the number until it has an exponent larger than 126 (i.e. (1 x 10^126.
D. The user can create a file in the JSON format with the metric name and value and supply it to CloudWatch


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?

A. Send the data using the put-metric-data command with the aggregate-values parameter
B. Send the data using the put-metric-data command with the average-values parameter
C. Send the data using the put-metric-data command with the statistic-values parameter
D. Send the data using the put-metric-data command with the aggregate –data parameter


A user has enabled detailed CloudWatch monitoring with the AWS Simple Notification Service. Which of the below mentioned statements helps the user understand detailed monitoring better?

A. SNS will send data every minute after configuration
B. There is no need to enable since SNS provides data every minute
C. AWS CloudWatch does not support monitoring for SNS
D. SNS cannot provide data every minute



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?

A. The size of a request is limited to 8KB for HTTP GET requests and 40KB for HTTP POST requests
B. The size of a request is limited to 128KB for HTTP GET requests and 64KB for HTTP POST requests
C. The size of a request is limited to 40KB for HTTP GET requests and 8KB for HTTP POST requests
D. The size of a request is limited to 16KB for HTTP GET requests and 80KB for HTTP POST requests


An AWS account owner has setup multiple IAM users. One IAM user only has CloudWatch access. He has setup the alarm action which stops the EC2 instances when the CPU utilization is below the threshold limit. What will happen in this case?

A. It is not possible to stop the instance using the CloudWatch alarm
B. CloudWatch will stop the instance when the action is executed
C. The user cannot set an alarm on EC2 since he does not have the permission
D. The user can setup the action but it will not be executed if the user does not have EC2 rights


A user is trying to understand the CloudWatch metrics for the AWS services. It is required that the user should first understand the namespace for the AWS services. Which of the below mentioned is not a valid namespace for the AWS services?

A. AWS/StorageGateway
B. AWS/CloudTrail
C. AWS/ElastiCache
D. AWS/SWF


A user is collecting 1000 records per second. The user wants to send the data to CloudWatch using the custom namespace. Which of the below mentioned options is recommended for this activity?

A. Aggregate the data with statistics, such as Min, max, Average, Sum and Sample data and send the data to CloudWatch
B. Send all the data values to CloudWatch in a single command by separating them with a comma. CloudWatch will parse automatically
C. Create one csv file of all the data and send a single file to CloudWatch
D. It is not possible to send all the data in one call. Thus, it should be sent one by one. CloudWatch will aggregate the data automatically


A user is sending the data to CloudWatch using the CloudWatch API. The user is sending data 90 minutes in the future. What will CloudWatch do in this case?

A. CloudWatch will accept the data
B. It is not possible to send data of the future
C. It is not possible to send the data manually to CloudWatch
D. The user cannot send data for more than 60 minutes in the future


A user has two EC2 instances running in two separate regions. The user is running an internal memory management tool, which captures the data and sends it to CloudWatch in US East, using a CLI with the same namespace and metric. Which of the below mentioned options is true with respect to the above statement?

A. The setup will not work as CloudWatch cannot receive data across regions
B. CloudWatch will receive and aggregate the data based on the namespace and metric
C. CloudWatch will give an error since the data will conflict due to two sources
D. CloudWatch will take the data of the server, which sends the data first


A user has configured an EC2 instance in the US-East-1a zone. The user has enabled detailed monitoring of the instance. The user is trying to get the data from CloudWatch using a CLI. Which of the below mentioned CloudWatch endpoint URLs should the user use?

A. monitoring.us-east-1.amazonaws.com
B. monitoring.us-east-1-a.amazonaws.com
C. monitoring.us-east-1a.amazonaws.com
D. cloudwatch.us-east-1a.amazonaws.com


Why? http://docs.aws.amazon.com/AmazonCloudWatch/latest/cli/SetupCLI.html "By default, the Amazon CloudWatch CLI uses the US East (N. Virginia) Region (us-east-1) with the monitoring.us-east-1.amazonaws.com service endpoint URL. "


A user is running a batch process on EBS backed EC2 instances. The batch process starts a few instances to process hadoop Map reduce jobs which can run between 50 – 600 minutes or sometimes for more time. The user wants to configure that the instance gets terminated only when the process is completed. How can the user configure this with CloudWatch?

A. Setup the CloudWatch action to terminate the instance when the CPU utilization is less than 5%
B. Setup the CloudWatch with Auto Scaling to terminate all the instances
C. Setup a job which terminates all instances after 600 minutes
D. It is not possible to terminate instances automatically


A user has created a launch configuration for Auto Scaling where CloudWatch detailed monitoring is disabled. The user wants to now enable detailed monitoring. How can the user achieve this?

A. Update the Launch config with CLI to set InstanceMonitoringDisabled = false
B. The user should change the Auto Scaling group from the AWS console to enable detailed monitoring
C. Update the Launch config with CLI to set InstanceMonitoring.Enabled = true
D. Create a new Launch Config with detail monitoring enabled and update the Auto Scaling group


A user has received a message from the support team that an issue occurred 1 week back between 3 AM to 4AM and the EC2 server was not reachable. The user is checking the CloudWatch metrics of that instance. How can the user find the data easily using the CloudWatch console?

A. The user can find the data by giving the exact values in the time Tab under CloudWatch metrics
B. The user can find the data by filtering values of the last 1 week for a 1 hour period in the Relative tab under CloudWatch metrics
C. It is not possible to find the exact time from the console. The user has to use CLI to provide the specific time
D. The user can find the data by giving the exact values in the Absolute tab under CloudWatch metrics