• Wget is a command-line Web client. It supports HTTP and FTP URLs, recursive retrievals, and HTTP proxies.

  • If you want to test your Squid cache in batch (from a cron command, for instance), you can use the echoping program, which will tell you (in plain text or via an exit code) if the cache is up or not, and will indicate the response times.

  • The squidclient is bundled with squid. It is very basic, but especially suited to working with Squid.

Stress-testing tools

  • curl-loader is a stress-testing tool for performance analysis

  • ApacheBenc (aka ab) is a very basic stress-testing software

Load Balancers

  • Pen is a simple load-balancer with session affinity for TCP-based protocols.

  • Layer-7 switching is a Layer-7 load-balancing engine for Linux. It's a young project, stemming off the more mature Keepalived.

  • Linux Virtual Server is a kernel-based layer 3-7 load balancer for Linux

HA Clusters

  • Keepalived is a software suite that implements HA (via VRRP) and status monitoring with failover capabilities. It's focused on Linux, support for other OSes is unclear.

  • VRRPd is aimple implementation of VRRPv2


Availability monitoring

  • Nagios is a very popular open-source enterprise monitoring platform.

Performance monitoring

  • Munin is a very flexible platform for collecting long-term performance data

  • Cacti is especially suited for collecting SNMP-basd data

  • RRDtool is the grandparent of F/OSS performance monitoring solutions

  • SqStat is an alternate frontend using the cache manager interface to collect and display real-time data.

Logfile Analysis

Rather than maintain the same list in two places, please see the Logfile Analysis Scripts page on the Web server.

  • Squeezer is a logfile analysis software aimed at measuring Squid's performance

SGI's Performance Co-Pilot

Jan-Frode Myklebust writes:

I use Performance CoPilot from for keeping track of squid and server performance. It comes by default with a huge number of system performance metrics, and also has a nice plugin (PMDA, Performance Metrics Domain Agent) for collecting metrics from the squid access.log.

i.e. it can collect historic, or show live how many requests/s or byte/s squid is answering of type:

  • total
  • get
  • head
  • post
  • other
  • le3k le10k le30k le100k le300k le1m le3m gt3m unknown
  • le3k le10k le30k le100k le300k le1m le3m gt3m unknown
  • le3k le10k le30k le100k le300k le1m le3m gt3m unknown

and also combine this with system level metrics like load, system cpu time, cpu i/o wait, per partition byte/s, network interface byte/s, and much more..

Because of it's historic logs of all this, it's great for collecting the performance numbers during high activity, and then replaying it to analyse what goes wrong later on.

Configuration Tools

  • Kenichi Matsui has a simple perl script which generates a 3D hierarchy map (in VRML) from squid.conf.

Squid add-ons

  • transproxy is a program used in conjunction with the Linux Transparent Proxy networking feature, and ipfwadm, to intercept HTTP and other requests. Transproxy is written by John Saunders <john AT nlc DOT net DOT au>

  • A redirector package from Iain Lea <iain AT ecrc DOT de> to allow Intranet (restricted) or Internet (full) access with URL deny and redirection for sites that are not deemed acceptable for a userbase all via a single proxy port.

  • Junkbusters Corp has a copyleft privacy-enhancing, ad-blocking proxy server which you can use in conjunction with Squid.

  • Squirm is a configurable, efficient redirector for Squid by Chris Foote <chris AT senet DOT com DOT au>.

  • Pedro L Orso <orso AT ineparnet DOT com DOT br> has adapated the Apache's htpasswd into a CGI program called chpasswd.cgi.

  • jesred by Jens Elkner <elkner AT wotan DOT cs DOT Uni-Magdeburg DOT de>.

  • SquidGuard is a free (GPL), flexible and efficient filter and redirector program for squid. It lets you define multiple access rules with different restrictions for different user groups. SquidGuard uses squid standard redirector interface.

  • The Smart Neighbour (URL disappeared) (or 'Central Squid Server' - CSS) is a cut-down version of Squid without HTTP or object caching functionality. The CSS deals only with ICP messages. Instead of caching objects, the CSS records the availability of objects in each of its neighbour caches. Caches that have smart neighbours update each smart neighbour with the status of their cache by sending ICP_STORE_NOTIFY/ICP_RELEASE_NOTIFY messages upon storing/releasing an object from their cache. The CSS maintains an up to date 'object map' recording the availability of objects in its neighbouring caches.
  • The Cerberian content filter is a very flexible URL rating system with full Squid integration provided by MARA Systems AB. The service requires a license (priced by the number of seats) but evaluation licenses are available.

Ident Servers

For Windows NT, Windows 95/98, and Unix.

Cacheability Validators

The Cacheability Engine is a python script that validates an URL, analyzing the clues a web server gives to understand how cacheable is the served content. An online tool is available at

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SquidFaq/RelatedSoftware (last edited 2013-04-11 08:35:53 by FrancescoChemolli)