A company operates a high-traffic web application with backend services hosted on EC2 instances behind an Application Load Balancer (ALB). During peak hours, the application experiences intermittent 5xx errors and increased latency, even though individual EC2 instance CPU utilization remains low. Analysis of network metrics shows a high number of dropped packets at the network interface level for the EC2 instances. The network engineer suspects that the instances are hitting network limits for packet processing. Which EC2 instance attribute can be modified to increase the maximum packets per second (PPS) and overall network bandwidth for the instances?
- AEnabling IPv6 on the instance's network interface.
- BChanging the instance type to one with higher network performance.
- CIncreasing the instance's Elastic Block Store (EBS) volume size.
- DAdjusting the TCP window size in the operating system.
Show answer & explanationAnswer & explanation
Correct answer: B. Changing the instance type to one with higher network performance.
Different EC2 instance types are designed with varying network performance capabilities, including maximum packets per second (PPS) and overall bandwidth. If instances are hitting network limits, changing to a larger instance type or one specifically optimized for network performance (e.g., network-optimized or compute-optimized instances with higher network capabilities) is the most direct solution to increase PPS and bandwidth.
Why the other options are wrong
- A. Enabling IPv6 adds addressing capability but does not inherently increase the underlying network hardware's PPS or bandwidth limits.
- C. EBS volume size affects storage I/O performance, not network PPS or bandwidth.
- D. Adjusting TCP window size can optimize TCP flow control, but it cannot overcome the fundamental hardware limits of the instance's network interface for PPS or bandwidth.
EC2 Network Performance Scaling
Scaling EC2 instance network performance by selecting appropriate instance types that offer higher maximum packets per second (PPS) and overall network bandwidth.
- Instance types dictate network limits.
- Higher network performance instances exist (e.g., C5n, M5n).
- Crucial for high-throughput or packet-intensive applications.
Memory trick: To boost your EC2 network, upgrade the instance type, not just the software.