NAME

       approx - proxy server for Debian archive files

SYNOPSIS

       approx [OPTION]...

DESCRIPTION

       approx  responds  to  HTTP  requests  made  by apt-get(8).  It maintains a cache of Debian
       archive files that have been previously downloaded, so that it can respond  with  a  local
       copy when possible.  If a file not in the cache is requested, approx will download it from
       a remote Debian repository and deliver the contents to the client, simultaneously  caching
       it for future use.

OPTIONS

       -c file, --config file
              Specify an additional configuration file.  May be used multiple times.

USAGE

       approx is invoked by inetd(8).

EXAMPLES

       Suppose that a client machine's /etc/apt/sources.list file contains the following lines:

              deb     http://apt:9999/debian    testing main
              deb     http://apt:9999/security  testing/updates main
              deb-src http://apt:9999/debian    unstable main

       In  this  example,  apt is the hostname of the approx server machine on the local network.
       Each distribution, such as "debian" or "security", is mapped to a remote repository in the
       approx server's configuration file.

       For example, the approx.conf file on the approx server might contain the lines

              debian   http://ftp.debian.org/debian
              security http://security.debian.org

       The mapping scheme is very simple.  If the approx.conf file contains the line

              repository     http://remote-host/initial/path

       then any request to the approx server of the form

              http://approx-server/repository/rest/of/URL

       is rewritten to

              http://remote-host/initial/path/rest/of/URL

       when there is a "cache miss", and that file is cached as

              /var/cache/approx/repository/rest/of/URL

       (Note  that the repository name on the left-hand side is not included in the rewritten URL
       unless it is explicitly mentioned in the right-hand side's initial path.)

FILES

       /etc/approx/approx.conf
              Configuration file for approx and related programs.

       /var/cache/approx
              Default cache directory for archive files.

SEE ALSO

       approx.conf(5), inetd(8), approx-import(8), apt-get(8), sources.list(5)

AUTHOR

       Eric Cooper <ecc@cmu.edu>

                                             May 2011                                   APPROX(8)