NAME

       network-test - check the network and test if everything is fine

SYNOPSIS

       network-test

DESCRIPTION

       The  network-test  program will test your system's network configuration using basic tests
       and providing both information (INFO), warnings (WARN) and possible errors (ERR) based  on
       the results of these tests.  It will check and report on:
              * Status of the network interfaces of the system including: link status,
               IP addressing and number of transmitted packets and error rates.

              * Accessibility to configured routes to external networks,
                including the default network route, checking the routers configured
                to give access to the network

              * Proper host resolution, testing DNS resolution against a known host.

              *  Proper network connectivity, testing reachability of remote hosts using ICMP and
              simulating a web connections to a remote web server (the web server  used  for  the
              tests can be configured through the environment, see below)

       The program does not need special privileges to run as it does not do any system change.

       However, the behaviour of the program when running as an unprivileged user is not the same
       as running as  system  administrator  (i.e.  root).  If  the  program  is  run  as  system
       administrator it will try to run some tools that are only available to it to speed up some
       of the tests.

       The program relies on the use of ip, netstat, ifconfig, arp and  (when  running  as  root)
       ethtool  or  mii-tool,  to  obtain information about the system's networking configuration
       (status of available interfaces and configured network routes). It also  uses  ping,  host
       and  nc  (netcat)  to  do  tests  of the network connectivity and ensure that the host can
       connect to the Internet.

ENVIRONMENT

       The program will, by default, check www.debian.org and its associated web server.  If  you
       want to use a different check host you can setup the environment as follows:

       CHECK_HOST
              The name of a host to use when testing DNS resolution.

       CHECK_IP_ADRESS
              The IP address of the host defined in CHECK_HOST

       CHECK_WEB_HOST
              The web server to use for testing purposes when testing network connectivity.

       CHECK_WEB_PORT
              The web server port of server CHECK_WEB_HOST that will be used for testing.

EXIT STATUS

       The program will exit with error (1) if any of the network checks fail.

BUGS

       This  program  does not have super cow powers so it is unable to fix the errors by itself.
       It is also unable to detect if the network is failing due to a local firewall policy  been
       in  place  so make sure you check your system logs with dmesg (1) to detect if some of the
       active tests are being dropped due to your local firewall.

       Other known issues that might make the program not work reliable are:

              * IPv6: The program does not yet explicitly handle IPv6 only  hosts,  some  of  the
              tests might be biased towards IPv4 and might fail in IPv6 environments.

              *  Proxies:  The program does not check network connectivity for hosts that connect
              through the Internet using a proxy gateway for services. The program  might  report
              issues  in  hosts  using  proxies  even  when  these  might connect to the Internet
              properly through proxied services.

              * Firewall environments: some of the tests rely on direct connectivity to  external
              hosts,  which  are  tested using ICMP queries (through the use of ping. These tests
              might fail in hosts installed in networking environments with firewalls that  block
              outbound ICMP communication.

SEE ALSO

       ip  (8),  netstat  (8), ifconfig (8), ethtool (8), mii-tool (8), ping (8), nc (1) and host
       (1).

AUTHOR

       network-test  was  written  by  Javier  Fernandez-Sanguino  for   the   Debian   GNU/Linux
       distribution.

COPYRIGHT AND LICENCE

       Copyright (C) 2005-2011 Javier Fernandez-Sanguino <jfs@debian.org>.

       This program is free software; you can redistribute it and/or modify it under the terms of
       the GNU General Public License as  published  by  the  Free  Software  Foundation;  either
       version 2, or (at your option) any later version.

       On   Debian  systems,  a  copy  of  the  GNU  General  Public  License  may  be  found  in
       /usr/share/common-licenses/GPL.