Coverage
Here you will find instructions for downloading the software and its related documentation.
Perl
Perl is probably already installed on your machine, but you should at least check the version you are using. It is highly recommended that you have at least Perl version 5.004. You can get the latest perl version from http://www.perl.com/ . Try the direct download link http://www.perl.com/pace/pub/perldocs/latest.html . You can get Perl documentation from the same location (although copious documentation is included in the downloaded Perl distribution).
Apache
Get the latest Apache webserver and documentation from http://www.apache.org . Try the direct download link http://www.apache.org/dist/ .
mod_perl
Get the latest mod_perl sources and documentation from http://perl.apache.org . Try the direct download link http://perl.apache.org/dist/ .
Source/Binary Distributions: http://perl.apache.org/distributions.html
RPM: http://perl.apache.org/rpm/
Debian users will find Perl, Apache and mod_perl are available as .deb files on official image CDs or from the Debian web site http://www.debian.org . The Debian distribution also contains many additional Perl and Apache libraries and modules.
Squid - Internet Object Cache
http://squid.nlanr.net/
Squid Linux 2.x Redhat RPMs : http://home.earthlink.net/~intrep/linux/
thttpd - tiny/turbo/throttling HTTP server
http://www.acme.com/software/thttpd/
mod_proxy_add_forward
Ask Bjoern Hansen has written a mod_proxy_add_forward.c module for Apache that sets the X-Forwarded-For field when doing a ProxyPass, similar to what Squid does. His module is at: http://modules.apache.org/search?id=124, at ftp://ftp.netcetera.dk/pub/apache/mod_proxy_add_forward.c or http://www.cpan.org/authors/id/ABH/mod_proxy_add_forward.c
complete with instructions on how to compile it in and whatnot.
httperf - webserver Benchmarking tool
http://www.hpl.hp.com/personal/David_Mosberger/httperf.html
ab - ApacheBench
Comes with the Apache distribution.
mod_backhand -- load balancing for Apache
http://www.backhand.org/mod_backhand/
High-Availability Linux Project
You will find the definitive guide to load balancing techniques at the High-Availability Linux Project site -- http://www.henge.com/~alanr/ha/
More load balancing URLs:
lbnamed - a load balancing name server written in Perl, by Roland Schemers http://www.stanford.edu/~riepel/lbnamed/ http://www.stanford.edu/~riepel/lbnamed/bof.talk/ http://www.stanford.edu/~schemers/docs/lbnamed/lbnamed.html
Network Address Translation and Networks: Virtual Servers (Load Balancing) http://www.csn.tu-chemnitz.de/~mha/linux-ip-nat/diplom/node4.html#SECTION00043100000000000000
Linux Virtual Server Project http://www.linuxvirtualserver.org/
Efficient Support for P-HTTP in Cluster-Based Web Servers. (with Mohit Aron and Willy Zwaenepoel.) In Proceedings of the USENIX 1999 Annual Technical Conference, Monterey, CA, June 1999. http://www.cs.rice.edu/~druschel/usenix99lard.ps.gz http://www.usenix.org/publications/library/proceedings/usenix99/full_papers/aron/aron_html/index.html
The latest ip filter includes some simple load balancing code, that allows a round-robin distribution onto several machines via ipnat. That may be a simple solution for a few specific load problem. http://coombs.anu.edu.au/~avalon/ipf3.4beta3.tgz
Apache::Request
Get it from CPAN at $CPAN/authors/id/DOUGM/libapreq-x.xx.tar.gz or from http://perl.apache.org/dist/libapreq-x.xx.tar.gz . (replace x.xx with the current version)
DataBases
Low-Cost Unix Database Differences http://www.toodarkpark.org/computers/dbs.html
My collection of various links to databases implementations http://stason.org/TULARC/webmaster/db.html