Introduction

Overview

LiteSpeed Web Server is an Apache-interchangeable, high performance, secure, easy-to-use web server. It can handle thousands of concurrent connections with a small memory footprint. Its security features also make it much less vulnerable to various attacks.

LiteSpeed Exclusive Features

Apache Drop-In Replacement
HTTP/2 Support
QUIC Support
Zero Downtime
Anti-DDoS Advances
Event-Driven Architecture

Features

HTTP/1.1
- HTTP/2
- HTTP 1.0/1.1 compliant
- Scripting Languages: PHP, Perl, Ruby, Python, Java, etc...
- Server APIs: LiteSpeed SAPI (LSAPI), CGI, FCGI, AJPv13, Proxy
- HTTPS
- IPv4 and IPv6
- Unlimited IP and name-based virtual hosting
- Unlimited concurrent connections
- GZIP compression
- Support for SPDY/2, 3, and 3.1
- WebSocket proxying
- Runs on Linux, FreeBSD, MacOSX, Solaris
Performance & Scalability
- Event-driven architecture
- Hundreds of thousands of concurrent connections
- Tiny memory footprint
- Sendfile()
- Asynchronous I/O support
- LiteSpeed's exclusive server API (LSAPI) delivers the best dynamic content performance
- Unrivaled PHP suEXEC performance for shared hosting
- Three different PHP process modes for different needs and abilities
- Static content up to 5x faster than Apache
- Dynamic content up to 40x faster than Apache
- HTTPS 3x faster than Apache
- OCSP stapling
- Built-in page caching
- Turbocharge Magento and other web applications with ESI support
- Advanced .htaccess caching removes performance bottlenecks associated with .htaccess use in Apache
- CloudLinux LVE compatibility
- Increases scalability of web applications
- Separation of server and web applications allows for buffering of requests and responses, leading to better handling of multiple connections
- Just in time configuration cuts restart time
- CPU affinity allows for greater use of CPU cache
Apache Compatibility
- Reads Apache's configuration files directly
- Drop-in Apache replacement for cPanel, Plesk, DirectAdmin, Interworx, etc.
- Full .htaccess support
- Compatible with Apache core modules
Security
- Built-in anti-DDoS connection and bandwidth throttling
- mod_security compatibility
- Compatibility with Atomic Secured Linux and Atomicorp Realtime ModSecurity Rules
- Anti SSL BEAST and renegotiation attack capabilities
- Strict HTTP request validation
- Denies buffer-overrun attempts
- PHP/Ruby/CGI/FCGI/LSAPI suEXEC
- CloudLinux CageFS compatibility
- External application and full server chroot ability
High Availability
- Apply changes with zero downtime
- Zero downtime server software upgrade
- Recovers from service failure instantly
Ease of Use
- Control panel plugins (cPanel, DirectAdmin, and Plesk)
- Officially supported by cPanel
- Intuitive WebAdmin console GUI
- Virtual host templates for easy configuration
- Real-time service monitoring
Advanced Features
- Easily run multiple versions of PHP on one server
- MS FrontPage Server Extensions
- Geo-IP lookup
- Stream logs to external logger
- Custom log formatting
- Backend load balancing
- mp4/flv streaming