ESSIDSCAN(8) Commands ESSIDSCAN(8)NAME
essidscan - scan for ESSID corresponding to available WLAN access points
SYNOPSIS
In /etc/network/interfaces:
mapping <interface> script essidscan
DESCRIPTION
The essidscan utility is used to tell the ifup and ifdown utilities about the current SSID of the WLAN currently being accessed. It can be
used to map the SSID name to an iface stanza.
CONFIGURATION
A sample /etc/network/interfaces may look like this:
mapping hotplug
script /etc/network/essidscan
map SSIDONE wlan-work
map SSIDTWO wlan-work
map HOME
iface wlan-work inet dhcp
wireless-key 1234-5678-9ABC-DEF0-1234-5678-9A
wireless-keymode restricted
iface HOME inet static
address 192.168.2.4
netmask 255.255.255.0
gateway 192.168.2.1
wireless-essid HOME
wireless-key s:somepassword
wireless-keymode open
iface DEFAULT inet dhcp
FILES
/etc/network/interfaces
the interfaces definition file
/etc/network/run/ifstate
a record of the current state of the interfaces, managed by ifup and ifdown
SEE ALSO interfaces(5)ifscheme(8)ifup(8)ifdown(8)AUTHORS
Tor Slettnes <tor@slett.net>
ESSIDSCAN(8)
Check Out this Related Man Page
IFSCHEME(8) Commands IFSCHEME(8)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 inter-
faces(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 inter-
face>-<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 suc-
cessfully 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)