Resolution of Metric Data for Analyzing Legacy Application on Amazon EC2 Instance

Correct Answer: C.

Amazon CloudWatch retains metric data as follows:

Data points for high-resolution custom metrics.

With a period of less than 60 seconds are available for 3 hours.

Data points with a period of 60 seconds are available for 15 days.

Data points with a period of 300 seconds are available for 63 days.

Data points with a period of 3600 seconds are available for 455 days.

Data Points that are published with a shorter period are aggregated to retain for longer periods.

In the above case, data was published with a standard resolution of 1 minute 30 days back.

So, Amazon CloudWatch will aggregate 1 min data to a resolution of 5 mins (300 secs) and retain it for 63 days.

Post 63 days, the resolution will be changed to 1 hour.

Option A is incorrect as only after 63 days, data is aggregated with resolution as 60 mins.

Option B is incorrect as this is an invalid resolution time frame.

Option D is incorrect as Data with a resolution of 1 min is retained only for 15 days.

Post 15 days data is aggregated and can be retrieved with 5 mins resolution.

For more information on the retention period for metrics, refer to the following URL,

https://docs.amazonaws.cn/en_us/AmazonCloudWatch/latest/monitoring/cloudwatch_concepts.html

Amazon CloudWatch is a monitoring service offered by AWS that collects and stores metric data and logs from various AWS resources such as EC2 instances, RDS instances, and Lambda functions. CloudWatch provides a set of pre-defined metrics, as well as the option to publish custom metrics.

In this scenario, the IT firm has deployed a legacy application on an EC2 instance, and the Operations Team wants to analyze custom metric data that was published 30 days back with a standard resolution to Amazon CloudWatch. The Team Lead is concerned about the resolution of metric data.

The resolution of metric data refers to the frequency at which metric data is collected and sent to CloudWatch. The resolution can be set to 1 minute, 5 minutes, or 1 hour. When you publish a custom metric to CloudWatch, you can specify the resolution for that metric.

In this scenario, the custom metric data was published with a standard resolution, which means it was likely published with the default resolution of 5 minutes. Therefore, the correct statement depicting the resolution of metric data would be C. Metric Data will be retrievable with a resolution of 5 mins.

Option A is incorrect because a resolution of 60 minutes would mean that metric data is collected and sent to CloudWatch once per hour, which is not the default resolution for custom metrics.

Option B is also incorrect because a resolution of 15 minutes is not the default resolution for custom metrics. Custom metrics can be published with a resolution of 1 minute or 5 minutes.

Option D is incorrect because a resolution of 1 minute is possible for custom metrics, but it is not the default resolution for custom metrics, which is 5 minutes.