Nginx Log Rotation & Compression Setup Guide

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Prerequisites

• Check available disk space

df -h /

• Verify gzip is installed

which gzip

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1. Backup Current Configuration

sudo cp /etc/logrotate.d/nginx /etc/logrotate.d/nginx.bak

2. Edit Logrotate Configuration

sudo nano /etc/logrotate.d/nginx

Replace contents with (log file extensions may vary on different servers; hence revise and edit where needed):

/etc/nginx/log/*.log /etc/nginx/log/*.access /etc/nginx/log/*.error /var/log/nginx/*.log {
    daily
    missingok
    rotate 14
    compress
    # delaycompress # Uncomment this line to enable delaycompress (log files will be compressed / zipped starting from *.2 onwards)
    notifempty
    create 0640 www-data root
    sharedscripts
    postrotate
        [ -f /var/run/nginx.pid ] && kill -USR1 $(cat /var/run/nginx.pid)
    endscript
}

3. Fix Permissions (Optional)

sudo chmod 640 /etc/nginx/log/*
sudo chown www-data:root /etc/nginx/log/*

4. Test Configuration

Dry run to check for errors

sudo logrotate -d /etc/logrotate.d/nginx

Force immediate rotation

sudo logrotate -vf /etc/logrotate.d/nginx

5. Verify Results

ls -lh /etc/nginx/log/

🕘 6. Set Up Cron Job to Delete Old Logs

Create cleanup script (optional, but more maintainable)

sudo nano /usr/local/bin/nginx-log-cleanup.sh

Paste this into the file:

#!/bin/bash

# Number of days to keep logs
RETENTION_DAYS=30

# Log directories to clean
LOG_DIRS=(
    "/var/log/nginx"
    "/etc/nginx/log"
)

for DIR in "${LOG_DIRS[@]}"; do
    find "$DIR" -type f -name "*.gz" -mtime +$RETENTION_DAYS -exec rm -f {} \;
done

Make it executable:

sudo chmod +x /usr/local/bin/nginx-log-cleanup.sh

Schedule it via cron (runs daily at 2:30am):

sudo crontab -e

Add this line:

30 2 * * * /usr/local/bin/nginx-log-cleanup.sh >> /var/log/nginx-cleanup-cron.log 2>&1

Optional: Monitor cron logs

Check this log to ensure the cron job runs correctly:

tail -f /var/log/nginx-cleanup-cron.log

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What Does 30 2 * * * Mean?

The cron expression 30 2 * * * breaks down as:

┌───────────── Minute (0 - 59)
│ ┌───────────── Hour (0 - 23)
│ │ ┌───────────── Day of Month (1 - 31)
│ │ │ ┌───────────── Month (1 - 12)
│ │ │ │ ┌───────────── Day of Week (0 - 7) (Sunday = 0 or 7)
│ │ │ │ │
│ │ │ │ │
30 2 * * *

Meaning:

• 30 → at 30 minutes past the hour
• 2 → at 2 AM
• * → every day of the month
• * → every month
• * → every day of the week

✅ This means the task runs at 2:30 AM every day.