Performance bottleneck identification in Nginx - Mini Project: Build & Apply

Performance Bottleneck Identification with Nginx

📖 Scenario: You are a system administrator for a small website. Recently, the website has been slow, and you want to find out what is causing the delay. You will use Nginx logs and configuration to identify the performance bottleneck.

🎯 Goal: Learn how to set up Nginx logging, configure a simple status page, and analyze logs to find slow requests causing performance issues.

📋 What You'll Learn

Create a basic Nginx access log format

Enable the Nginx stub_status module for monitoring

Use log format to capture request time

Analyze logs to find slow requests

💡 Why This Matters

🌍 Real World

Web servers often slow down due to some requests taking too long. Identifying these slow requests helps fix performance issues.

💼 Career

System administrators and DevOps engineers use Nginx logs and status modules to monitor and improve web server performance.

1

Set up Nginx access log with request time

Create an Nginx configuration snippet that defines a log format called main which logs the client IP ($remote_addr), request time in seconds ($request_time), and the requested URI ($request_uri). Then set the access log to use this main format and write to /var/log/nginx/access.log.

Nginx

# Define log format 'main' and set access_log to '/var/log/nginx/access.log' using 'main'
# Your code here

Need a hint?

Use log_format directive to define the format. Then use access_log directive to specify the log file and format.

2

Enable Nginx stub_status for monitoring

Add a location block for /nginx_status inside the server block that enables the stub_status module by setting stub_status on;. This will allow you to check basic Nginx performance metrics.

Nginx

log_format main '$remote_addr - $request_time - $request_uri';
access_log /var/log/nginx/access.log main;

# Add location /nginx_status with stub_status on
# Your code here

Need a hint?

Use a location block with stub_status on; and restrict access to localhost with allow and deny.

3

Analyze logs to find slow requests

Write a shell command that uses awk to read /var/log/nginx/access.log and print lines where the request time (third field) is greater than 1 second. Use awk '$3 > 1' to filter.

Nginx

log_format main '$remote_addr - $request_time - $request_uri';
access_log /var/log/nginx/access.log main;

location /nginx_status {
    stub_status on;
    allow 127.0.0.1;
    deny all;
}

# Write awk command to filter slow requests > 1 second
# Your code here

Need a hint?

Use awk to check the third field (request time) and print lines where it is greater than 1.

4

Display slow requests output

Run the command awk '$3 > 1' /var/log/nginx/access.log and print the output to show slow requests that took more than 1 second.

Nginx

log_format main '$remote_addr - $request_time - $request_uri';
access_log /var/log/nginx/access.log main;

location /nginx_status {
    stub_status on;
    allow 127.0.0.1;
    deny all;
}

# Run the awk command and print output
# Your code here

Need a hint?

Run the awk command to see lines with request time greater than 1 second.