NAME

       ifscheme - scheme control for network interfaces

SYNOPSIS

       ifscheme [-v] [[-s] newscheme]

       mapping <interface> script ifscheme-mapping

DESCRIPTION

       ifscheme allows you to change network configuraton schemes or query the current scheme. It
       integrates with the ifup(8) command and interfaces(5).  For example, you  might  use  this
       program to configure a "home" scheme and a "work" scheme for a network device on a laptop.
       When you move between home and work, a simple command can reconfigure your networking.

       If you run the program with no parameters, it will tell what the  current  network  scheme
       is.

       The  ifscheme-mapping  utility  is  used  to  tell the ifup and ifdown utilities about the
       current scheme.

OPTIONS

       -v

       --verbose
              Run in verbose mode. This is passed in to the ifup and ifdown programs as well.

       -l

       --list list all schemes available/defined in /etc/network/interfaces.

       newscheme

       -s newscheme

       --scheme newscheme
              Change to a new network configuration scheme.  When the scheme is changed,  network
              interfaces that were using the old scheme will be taken down and brought back up to
              use the new configuration scheme. -s or --scheme are mandatory if newscheme  begins
              with a -.

CONFIGURATION

       To  make  the  program  do  anything  useful  when  a  scheme  is  selected, you must edit
       /etc/network/interfaces to add a mapping for the interface (or  interfaces)  that  can  be
       controlled  on a per-scheme basis. Suppose you want to control eth0 in this way. You might
       have an existing eth0 configuraton in there, such as:

         auto eth0

         iface eth0 inet static
            address 192.168.1.5
            netmask 255.255.255.0
            gateway 192.168.1.1

       To change this so you can chose between static routing  and  dhcp,  replace  it  with  the
       following (it helps to ifdown the interface first).

         auto eth0

         mapping eth0
            script ifscheme-mapping

         iface eth0-home inet static
            address 192.168.1.5
            netmask 255.255.255.0
            gateway 192.168.1.1

         iface eth0-work inet dhcp

       Now  if  you  run  "ifscheme  home"  and  ifup  the  interface,  you'll  get the eth0-home
       configuration stanza. If you run "ifscheme work", it will  be  changed  to  the  eth0-work
       stanza.  You  can  add  additional stanzas as desired, but the label must always be of the
       form <hardware interface>-<scheme name>.

       If you have a second interface  (perhaps  a  wireless  network  card  on  eth1),  you  can
       duplicate the above for that interface, changing the eth0 and the configuration details as
       appropriate, but remember to add an iface stanza for every  scheme  name  for  the  second
       interface.

FILES

       /etc/network/interfaces
              the interfaces definition file

       /etc/network/run/scheme
              the current scheme

       /etc/network/run/ifstate
              a record of the current state of the interfaces, managed by ifup and ifdown

BUGS

       All schemed interfaces will have the same scheme.

       Any  schemed  interface  which  does  not  have an entry for the current scheme and is not
       configured when the scheme is changed will not  be  successfully  configured  when  it  is
       brought up.

SEE ALSO

       interfaces(5) ifup(8) ifdown(8)

DISTRIBUTION

       Redistribution is subject to the GNU public license.

AUTHORS

       Joey Hess <joey@kitenet.net>, Peter Wilson <pwilson@cs.hmc.edu>

                                                                                      IFSCHEME(8)