ifscheme - scheme control for network interfaces
ifscheme [-v] [[-s] newscheme]
- mapping <interface> script
allows you to change network configuraton schemes or query the
current scheme. It integrates with the ifup
(8) command and
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
The ifscheme-mapping utility is used to tell the ifup and ifdown utilities about
the current scheme.
- Run in verbose mode. This is passed in to the ifup and
ifdown programs as well.
- list all schemes available/defined in
- -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 -.
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:
iface eth0 inet static
To change this so you can chose between static routing and dhcp, replace it with
the following (it helps to ifdown the interface first).
iface eth0-home inet static
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
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.
- the interfaces definition file
- the current scheme
- a record of the current state of the interfaces, managed by
ifup and ifdown
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.
Redistribution is subject to the GNU public license.
Joey Hess <email@example.com>, Peter Wilson