vincentmli / proxyos

ProxyOS is an open source Linux distribution based on Centos, but focus on layer 4 and layer 7 network load balancing. Most of the C code is inherited from various open source project including Linux virtual server, nginx/tengine, keepalived. the simple web management gui idea is inspired from redhat piranha, but completely rewritten to read/write keepalived and nginx configuration file.

The majority of the load balancing code has been used in Alibaba taobao.com to handle world most busy e-commerce web traffic and in China's number one cloud provider aliyun.

Some of the additional features differs from upstream project highlighted as below :

Layer 4 TCP virtual server load balancing

    SYNPROXY: Defence against syn flooding attack

    FULLNAT: full source and destination address translation to reduce network maintenances

Layer 7 HTTP/HTTPS load balancing

All features of Nginx 1.4 inherited plus<

    load balancing methods, e.g., consistent hashing, session persistence, upstream health check, and resolving upstream domain names on the fly

    Input body filter support. It's quite handy to write Web Application Firewalls using this mechanism

    Dynamic scripting language (Lua) support, which is very efficient and makes it easy to extend core functionalities

    Limits retries for upstream servers (proxy, memcached, fastcgi, scgi, uwsgi)

    Protects the server in case system load or memory use goes too high

    The number of worker processes and CPU affinities can be set automatically

    Request limit to prevent HTTP DDOS and whitelist support and more conditions are allowed in a single location

    Sends unbuffered upload directly to HTTP and FastCGI backend servers, which saves disk I/Os

    Logging enhancements. Syslog (local and remote), pipe logging and log sampling are supported

High-Availability and Virtual Router Redundancy Protocol (VRRP)

    All features of keepalived 1.2.13 inherited plus below

    Add tcp virtual server syn flooding protection configuration

    Add tcp virtual server source and destination address configuration

    Replace select with epoll for better I/O handling

WebUI configuration - easy to use WebUI configuration interface

Linux firewall - WebUI to configure iptables rules