Introduction

LiteSpeed Web Server (LSWS) is a high-performance web server that can be used as a drop-in replacement for Apache. It reads Apache configuration files directly, provides full .htaccess support, and is compatible with common control panels such as cPanel, Plesk, and DirectAdmin.

LSWS uses an event-driven architecture and is capable of handling a large number of concurrent connections with a small memory footprint.

Features

Protocols and Compatibility

• HTTP/1.0, HTTP/1.1, HTTP/2, and HTTP/3 (QUIC)
• GZIP, Brotli, and Zstd compression
• WebSocket proxying
• IPv4 and IPv6 support
• Unlimited IP-based and name-based virtual hosting
• HTTPS with OCSP stapling
• Support for PHP, Perl, Ruby, Python, and other scripting languages via LSAPI, CGI, FastCGI, and other interfaces

Performance and Scalability

• Event-driven architecture
• Low memory usage
• High concurrent connection capacity
• sendfile() and asynchronous I/O
• LiteSpeed Server Application Programming Interface (LSAPI) for dynamic content
• .htaccess caching
• ESI (Edge Side Includes) support
• CloudLinux LVE and CageFS compatibility

Apache Compatibility

• Support for Apache configuration directives and VirtualHost syntax
• Full .htaccess support including mod_rewrite
• Compatible with many Apache core modules
• Drop-in replacement for control panel-managed servers

Security

• Connection and bandwidth throttling
• mod_security compatibility
• Protection against common SSL attacks
• Strict HTTP request validation and buffer overrun prevention
• suEXEC support
• Chroot support

High Availability

• Zero-downtime configuration reloads, restarts, and software upgrades

Management

• WebAdmin Console for configuration and real-time monitoring
• Virtual host templates
• Support for multiple PHP versions
• Official control panel plugins

Additional Features

• MP4/FLV streaming
• Geo-IP lookup
• Custom logging
• Backend load balancing
• Prometheus exporter support