At present, many schools have built a campus network and connects to the Internet, but there are many bad information on the Internet. How to filter, prevent unhealthy websites from affecting students? Here is the following principles of zero cost, high-efficiency, talk about how to implement the Internet filtering function under free Linux. Set the proxy server campus network through Linux to use the Squid's frameworking server on the gateway. The first thing to install Linux, I use the easy-to-use Redhat Linux 7.2. When installing Redhat Linux 7.2, Squid is installed at the same time, we can use it simple configuration. Redhat Linux 7.2 After installation, the default is not running apache, so you can check the Squid, make sure the Squid proxy server works normally. Modify the /etc/squid/squid.conf configuration file. HTTP_PORT 3128 (Defines the port of the Squid listening to HTTP client request) Cache_mem 10 MB (ideal value can be used by Squid, 1/3 of the physical memory) cache_swap_low 95 cache_swap_low 90 maximum_object_size 4096 KB (greater than this value object will not be Storage) Cache_dir ufs / var / spool / squid / cache 200 16 256 (Specifies Squid to store the Switch Space Size and Its Directory Structure) ACL All SRC 192.168.1.1/24 (Definition All 192.168.1.1 Network Segment) http_acceaa Allow All (192.168.1.1 network segment client can use Squid agent Internet access) cache_effective_user squid (user and user group) cache_effective_group Squid (the remaining parameters can be used by default) [root @ Squid bin] # chmod 777 / var / Spool / Squid / Cache (Make / VAR / Spool / Squid / Cache directory is NOBOAY users, with write permissions) [root @ Squid bin] # Squid -z (manually established Squid cache catalog / var / spool / square) [root @ Squid bin] # /etc/rc.d/init.d/squid start (Start Squid, stop Squid with /etc/rc.d/init.d/squid stop) Test in the client, with Windows example. Run IE, click Tool, then click Internet Options, then click the Connection tab, click LAN Settings; in the LAN settings window, fill in the Squid server at the "address" IP address: 192.168.1.16, "3128" is filled in the "port", and then exit after it is determined. At this point, the client should browse the Internet, indicating that the Squid is running normally. The configuration of the filtering function is the configuration of the website filtering function. There are two configuration methods. Method First to ftp://k12linux.mesd.k12.or.us/pub/squidguard/ download rpm version of SquidGuard-1.2.0-3.i386.rpm.
