Is Nginx down today?

How to Contact Nginx Technical Support?

- Documentation at https://nginx.org/en/docs;

- Community mailing list at https://mailman.nginx.org/mailman/listinfo/nginx;

- Commercial support at https://www.nginx.com/support;

- Forum at https://forum.nginx.org;

- GitHub issues at https://github.com/nginx/nginx (for bugs);

- IRC channel #nginx on Libera.Chat.

Latest News and Current Information:

- Official Website - https://nginx.org;

- Documentation - https://nginx.org/en/docs;

- Blog - https://www.nginx.com/blog;

- GitHub - https://github.com/nginx/nginx;

- X (Twitter) - https://twitter.com/nginx;

- LinkedIn - https://www.linkedin.com/company/nginx;

- Download - https://nginx.org/en/download.html;

- Security Advisories - https://nginx.org/en/security_advisories.html;

- Commercial - https://www.nginx.com;

- Community - https://forum.nginx.org.

Nginx Outage: Web Server Service Not Responding

Service disruptions manifest as Nginx not starting, "502 Bad Gateway" errors, "503 Service Unavailable" messages, or complete web server failure.

- Check Nginx service status: `systemctl status nginx`;

- Restart Nginx: `sudo systemctl restart nginx`;

- Verify configuration syntax: `nginx -t`;

- Check error logs: `/var/log/nginx/error.log`;

- Verify port 80/443 not blocked;

- Check system resources available;

- Review process list: `ps aux | grep nginx`;

- Verify file permissions correct;

- Check disk space sufficient;

- Monitor server resource usage.

Configuration or Syntax Problem: Nginx Config File Errors

Configuration issues include "nginx: configuration file test failed" errors, syntax errors, directives invalid, or reload failing.

- Test config: `sudo nginx -t`;

- Check syntax in config files;

- Verify bracket/semicolon placement;

- Review recent configuration changes;

- Restore backup config if available;

- Check directive spelling correct;

- Verify paths exist and accessible;

- Review nginx.conf includes;

- Check file permissions readable;

- Validate SSL certificate paths.

502 Bad Gateway Fault: Nginx Cannot Connect to Upstream

Upstream connection problems include "502 Bad Gateway" errors, backend timeouts, PHP-FPM not responding, or proxy failures.

- Check upstream service running (PHP-FPM/app);

- Verify backend listening on correct port;

- Check upstream configuration correct;

- Increase proxy timeouts in config;

- Review upstream error logs;

- Verify socket file exists/permissions;

- Check firewall allows backend connection;

- Restart upstream service;

- Verify upstream not overloaded;

- Test backend connectivity directly.

SSL/TLS Certificate Issue: HTTPS Not Working on Nginx

Certificate problems include SSL handshake failures, "certificate expired" warnings, mixed content errors, or HTTPS not loading.

- Check certificate expiration date;

- Verify certificate paths in config;

- Renew Let's Encrypt certificate;

- Check certificate chain complete;

- Verify private key matches certificate;

- Test SSL: `openssl s_client -connect domain:443`;

- Check certificate permissions (readable);

- Verify SSL directives configured correctly;

- Review cipher suite compatibility;

- Check certificate trusted by browsers.

Performance or High Load Problem: Nginx Server Slow Response

Performance issues include slow page loading, high CPU usage, memory exhaustion, connection timeouts, or request queuing.

- Check server resource usage: `top/htop`;

- Optimize worker_processes setting;

- Increase worker_connections limit;

- Enable gzip compression;

- Implement caching strategies;

- Review access logs for traffic spikes;

- Check backend application performance;

- Optimize buffer sizes;

- Limit request rate with limit_req;

- Monitor concurrent connections.

404 Not Found or Path Issue: Nginx Cannot Find Files

File access problems include "404 Not Found" errors, static files missing, root directory wrong, or location blocks misconfigured.

- Verify root directory path correct;

- Check file exists at specified path;

- Review location block configuration;

- Check file permissions readable;

- Verify index directive configured;

- Check alias vs root directive usage;

- Review try_files directive;

- Check case sensitivity in paths;

- Verify symbolic links working;

- Test with absolute paths.

Access Control or Authentication Problem: Nginx Blocking Requests

Access restriction issues include "403 Forbidden" errors, IP blocking, basic auth failing, or deny rules misconfigured.

- Check allow/deny directives;

- Verify IP whitelist/blacklist correct;

- Review basic auth configuration;

- Check .htpasswd file exists/permissions;

- Verify client IP not blocked;

- Review access log for blocked IPs;

- Check file/directory permissions (755/644);

- Verify auth_basic directives;

- Test with allowed IP address;

- Review security module rules.

Reverse Proxy or Load Balancing Fault: Nginx Proxy Not Working

Proxy configuration problems include proxy_pass failing, upstream servers unreachable, load balancing broken, or header issues.

- Verify proxy_pass URL correct;

- Check upstream server reachable;

- Test backend connectivity: `curl backend:port`;

- Review upstream block configuration;

- Check proxy headers forwarded correctly;

- Verify load balancing method suitable;

- Monitor upstream server health;

- Check proxy timeouts configured;

- Review proxy buffer settings;

- Verify backend accepts proxied requests.

Log Files or Monitoring Issue: Nginx Logs Not Working

Logging problems include logs not writing, access.log empty, error.log missing, log rotation failing, or excessive log size.

- Check log file paths in config;

- Verify log directory permissions writable;

- Check disk space not full;

- Review log format directives;

- Verify logrotate configured correctly;

- Check access_log/error_log directives;

- Monitor log file sizes;

- Test logging: `tail -f /var/log/nginx/access.log`;

- Verify syslog configuration if used;

- Check log level severity set.

Virtual Host or Server Block Problem: Nginx Multiple Sites Not Working

Virtual hosting issues include wrong site loading, server_name not matching, default site serving, or subdomain routing broken.

- Check server_name directive correct;

- Verify DNS resolves to server IP;

- Review default_server configuration;

- Check sites-enabled symlinks exist;

- Verify listen directives unique/correct;

- Test with Host header: `curl -H "Host: domain.com"`;

- Check server block priority;

- Review include directives loading configs;

- Verify no conflicting configurations;

- Reload Nginx after changes.

Module or Plugin Problem: Nginx Modules Not Loading

Module functionality issues include third-party modules failing, dynamic modules not loading, missing module features, or compilation errors.

- Check module compiled/installed correctly;

- Verify load_module directive in config;

- Check module compatibility with version;

- Review module configuration syntax;

- Verify shared library paths correct;

- Check Nginx compiled with module support;

- Review module error messages;

- Test with module disabled;

- Verify dependencies installed;

- Recompile Nginx with required modules.

Cache or Static Content Fault: Nginx Caching Not Working

Caching problems include cache not serving content, stale cache, cache keys wrong, or purge failing.

- Verify proxy_cache_path configured;

- Check cache directory exists/writable;

- Review cache key configuration;

- Check cache validity settings;

- Monitor cache hit/miss ratio;

- Verify Cache-Control headers;

- Test cache purge functionality;

- Check cache size limits;

- Review bypass conditions;

- Clear cache manually if needed.

WebSocket or HTTP/2 Issue: Nginx Modern Protocol Support Problems

Protocol support problems include WebSocket connections failing, HTTP/2 not working, upgrade header issues, or connection downgraded.

- Enable HTTP/2: `listen 443 ssl http2`;

- Configure WebSocket upgrade headers;

- Check proxy_http_version 1.1;

- Verify Connection upgrade header;

- Check SSL required for HTTP/2;

- Review protocol compatibility;

- Test WebSocket connection separately;

- Verify browser supports HTTP/2;

- Check upstream supports WebSocket;

- Monitor protocol usage in logs.

Security or DDoS Problem: Nginx Under Attack

Security issues include DDoS attacks, rate limiting triggered, malicious requests, brute force attempts, or bot traffic.

- Implement rate limiting: limit_req_zone;

- Enable fail2ban for Nginx;

- Configure connection limits;

- Block malicious IPs/user-agents;

- Implement WAF rules (ModSecurity);

- Use geo-blocking if applicable;

- Monitor access logs for patterns;

- Enable request buffering limits;

- Implement CAPTCHA for suspected bots;

- Review security headers configured.

Rewrite Rules or Redirect Fault: Nginx URL Rewriting Not Working

Rewrite/redirect problems include infinite redirect loops, rewrite rules not matching, redirects to wrong URL, or regex errors.

- Test rewrite rules carefully;

- Check redirect loops (301/302);

- Verify regex patterns correct;

- Use return directive for simple redirects;

- Check rewrite flags (last/break/redirect);

- Test with curl to see redirects;

- Review rewrite log for debugging;

- Verify location block order;

- Check if/rewrite directive conflicts;

- Test regex at https://regex101.com.