Using the Squid Reverse Proxy to Improve eZ Publish Performance
Thursday 11 January 2007 11:23:00 am
Squid installation
To install Squid on a Linux system, use the apt-get application. You should also install the squidclient command line tool. Squid is also available in other package formats and on most other platforms. See the About Squid FAQ for a list of supported operating systems.
The following example shows the commands used to install Squid on Debian-based Linux systems using apt-get.
# apt-get install squid # apt-get install squid-client
To start Squid, run the following command:
# /etc/init.d/squid start
Squid configuration
After installing Squid, you must modify the configuration file to suit your installation. The configuration file shown below is the one used in the eZ performance lab.
# cat /etc/squid/squid.conf # eZ Publish cluster cache acl all src 0.0.0.0/0.0.0.0 visible_hostname babylonproxy.ezcluster.no icp_access allow all # Make Squid listen on port 80 http_port 80 # tell squid to contact the real webserver httpd_accel_host 192.168.0.3 httpd_accel_port 80 httpd_accel_uses_host_header off # Disable proxy support httpd_accel_with_proxy off http_access allow all
The significant settings in this file are http_port, http_accel_host and http_accel_port. The first defines the port on the Squid server that should be used. The latter two define the server and port where eZ Publish is installed.
If Squid is running on the same server as the eZ Publish installation, you would run Apache on, for example, port 81 and Squid on port 80. You would then change the http_accel_port value to 81.
Security
By default, Squid can act as both a proxy and a reverse proxy accelerator. You normally do not want the Squid server to be used as a proxy, as users would thus be able to set Squid to access other servers on the internet on the users' behalf. This would slow down the Squid server with unnecessary requests and create a security risk.
We only want Squid to allow access to the webservers (in our case, the eZ Publish webserver) we want to accelerate. The setting below ensures this.
httpd_accel_with_proxy off