APPROX(8) APPROX(8)
approx - proxy server for Debian archive files
approx [OPTION]...
approx listens for 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.
Over time, the approx server cache will grow to contain multiple,
unneeded versions of Debian packages. The gc_approx(8) program removes
these from the cache.
-f, --foreground
Run in the foreground instead of detaching as a daemon, and
print messages to standard error instead of the system log.
-v, --version
Display approx version information and exit.
By default, approx listens on port 9999 (for compatibility with
apt-proxy(8)). 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.)
/etc/approx/approx.conf
Configuration file for approx and related programs.
/var/cache/approx
Cache directory for archive files.
/etc/default/approx
This file is read by the init script /etc/init.d/approx that
starts approx. It can be used to set environment variables for
the approx daemon and its child processes, in particular
curl(1). For example, setting the http_proxy environment vari-
able will cause approx to use an upstream HTTP proxy when down-
loading from remote repositories.
approx.conf(5), update_approx(8), gc_approx(8), apt-get(8),
sources.list(5)
Eric Cooper <ecc [AT] cmu.edu>
November 2007 APPROX(8)