735dadf894
The kernel documentation is now restructured text. Convert the IP aliasing documentation and include it in the toplevel kernel documentation. - Fix heading adornments. - Correctly indent code snippets. - Limit line length to 72 characters inline with kernel documentation standards. - Add license identifier. Signed-off-by: Tobin C. Harding <me@tobin.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
49 lines
1.2 KiB
ReStructuredText
49 lines
1.2 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
|
|
|
|
===========
|
|
IP-Aliasing
|
|
===========
|
|
|
|
IP-aliases are an obsolete way to manage multiple IP-addresses/masks
|
|
per interface. Newer tools such as iproute2 support multiple
|
|
address/prefixes per interface, but aliases are still supported
|
|
for backwards compatibility.
|
|
|
|
An alias is formed by adding a colon and a string when running ifconfig.
|
|
This string is usually numeric, but this is not a must.
|
|
|
|
|
|
Alias creation
|
|
==============
|
|
|
|
Alias creation is done by 'magic' interface naming: eg. to create a
|
|
200.1.1.1 alias for eth0 ...
|
|
::
|
|
|
|
# ifconfig eth0:0 200.1.1.1 etc,etc....
|
|
~~ -> request alias #0 creation (if not yet exists) for eth0
|
|
|
|
The corresponding route is also set up by this command. Please note:
|
|
The route always points to the base interface.
|
|
|
|
|
|
Alias deletion
|
|
==============
|
|
|
|
The alias is removed by shutting the alias down::
|
|
|
|
# ifconfig eth0:0 down
|
|
~~~~~~~~~~ -> will delete alias
|
|
|
|
|
|
Alias (re-)configuring
|
|
======================
|
|
|
|
Aliases are not real devices, but programs should be able to configure
|
|
and refer to them as usual (ifconfig, route, etc).
|
|
|
|
|
|
Relationship with main device
|
|
=============================
|
|
|
|
If the base device is shut down the added aliases will be deleted too.
|