Pen is a load balancer for "simple" TCP-based protocols such as HTTP or SMTP. It allows several servers to appear as one to the outside. It automatically detects servers that are down and distributes clients among the available servers. This gives high availability and scalable performance.
| Tags | Internet Web Clustering/Distributed Networks Networking |
|---|---|
| Licenses | GPL |
| Operating Systems | POSIX Linux Solaris Mac OS X Windows |
| Implementation | C |


Release Notes: This release adds IPv6 support for backend servers as well as the listening socket. Protocols can be mixed and matched among IPv4, IPv6, and Unix domain sockets. GeoIP support was also updated for IPv6.


Release Notes: This release introduces support for Unix domain sockets in addition to Internet sockets. This new feature is available for the "main" listening socket as well as the control socket and allows access control using Unix file permissions. Documentation was updated to clarify what the control socket does.


Release Notes: This release adds support for GeoIP access lists. It is now possible to restrict access to the load balancer using syntax such as "acl 0 permit country CA" and "acl 0 deny country SE". These access control entries can be mixed with the usual IP-based ones.


Release Notes: The penctl and penlog utilities are now IPv6-compatible. The Automake configuration was updated. A clause was added to the license to explicitly permit distributing binaries linked with the openssl library.


Release Notes: SSL support has been updated.
19 Dec 2006 01:45
alternative XLB
Hi, sorry for the blatant advertising, but I just finished the first release of XLB, which is only for HTTP but includes a connection management and caching.
See http://sf.net/projects/xlb (http://sf.net/projects/xlb).
Thanks for feedback ;)