AWS Certified Advanced Networking – Specialty (ANS-C01)Network Management and OperationsMedium
A company is experiencing intermittent connectivity issues to an application hosted on an EC2 instance. Users report slow response times and occasional timeouts. The network engineer suspects packet loss or high latency. Which CloudWatch metric should the engineer examine first to investigate these issues?
- ACPUUtilization
- BStatusCheckFailed
- CNetworkPacketsLost
- DNetworkOut
Show answer & explanationAnswer & explanation
Correct answer: C. NetworkPacketsLost
NetworkPacketsLost is a specific CloudWatch metric that directly indicates packet loss, which can cause intermittent connectivity, slow response times, and timeouts. While other metrics might be related, this one directly addresses the suspected issue.
Why the other options are wrong
- A. CPUUtilization indicates the processing load on the instance, which can affect performance but isn't a direct indicator of network packet loss.
- B. StatusCheckFailed indicates issues with the instance itself or the underlying hardware, not necessarily packet loss on the network interface.
- D. NetworkOut measures the number of bytes sent by the instance, which indicates network activity but not necessarily loss or latency.
EC2 Network Metrics
Amazon EC2 provides several metrics through Amazon CloudWatch to monitor the network performance and health of instances.
- Metrics include NetworkIn, NetworkOut, NetworkPacketsIn, NetworkPacketsOut, and NetworkPacketsLost.
- Used for troubleshooting connectivity, performance, and resource utilization.
- Can be aggregated and visualized in CloudWatch dashboards.
Memory trick: When connection 'breaks,' check 'packets lost' first.