|  | 
 | 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. | 
 |  | 
 | o 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. | 
 | 	 | 
 |  | 
 | o Alias deletion. | 
 |   The alias is removed by shutting the alias down: | 
 |  | 
 |     # ifconfig eth0:0 down | 
 |                  ~~~~~~~~~~ -> will delete alias | 
 |  | 
 |   		   		    | 
 | o Alias (re-)configuring | 
 |  | 
 |   Aliases are not real devices, but programs should be able to configure and | 
 |   refer to them as usual (ifconfig, route, etc). | 
 |  | 
 |  | 
 | o Relationship with main device | 
 |  | 
 |   If the base device is shut down the added aliases will be deleted  | 
 |   too. |