|
Hopefully, this page is exactly what you are looking for, but if not, you can always find further assistance on Unix/Linux Forum!
IFUP(8) Network configuration IFUP(8)
NAME
ifup - start a preconfigured net interface.
ifdown - stop a (preconfigured) net interface.
ifstatus - show the state of a (preconfigured) net interface.
ifrenew - renews the dhcp lease on a net interface.
ifprobe - checks if the configuration for the interface has changed
SYNOPSIS
if{up,down,status,renew,probe} [ <configuration-name> ] <hardware-
description> [-o options ]
NOTATION
We use the terms configuration, interface and device in a dedicated
way. A device is always a piece of hardware representing a network
interface, a PCI or PCMCIA card or a USB device. An interface then is
the name of the network interface it gets from the kernel when the
device has been registered. A configuration is a set of parameters
which can be assigned to an interface like IP addresses or routes.
It is intentional that a configuration does not need to belong to an
interface, but to a device. For built-in devices there is most of the
time a fixed relation between devices and interfaces, but this is no
longer the case when using hotpluggable devices. With such devices
(like PCMCIA or USB) you cannot always know which interface name you
will get. So even if the interface name changes the interface to a cer-
tain device will always have the right setup.
DESCRIPTION
ifup is used to bring up a preconfigured interface for networking. It
is usually invoked by the network script at boot time or by the PCM-
CIA/hotplug system. It can also be used to start interfaces manually on
the command line. It activates the link, adds addresses and other
parameters and sets up the routes for an interface.
ifdown is used to set down the interface and flush all its addresses.
It is possible to let ifdown check the interface if it is still used
before setting it down. If configured it may then get rid of the using
processes or refuse setting it down. Have a look at /etc/sysconfig/netâ
work/config to enable this feature.
ifstatus checks if the interface and its routes were set up properly.
ifrenew is used to renew the dhcp lease on the desired interface with-
out shutting the interface down. It only restarts the corresponding
dhcpcd or dhclient process.
ifprobe checks if any of the configuration files for this interface
have been changed since the interface is up. Checked files are the cor-
responding ifcfg-*, ifroute-*, ifservices-* and common configuration
files config, dhcp and routes.
<hardware-description> may just be the interface name.
But it can be more. It describes the device of the interface to be set
up. As there is no fixed relation between devices and the names their
interfaces get from the kernel, it might be necessary to specify the
device exactly. The hardware-description may be the current interface
name, the MAC address or the bus location where the device resides. It
has to be compliant with the device naming rules as specified in
getcfg(8). ifup uses getcfg to obtain all missing information, for
example the interface name of a device with given hardware-description.
ifup uses getcfg also to get the best matching configuration for the
interface. Every configuration is stored in files below /etc/sysconâ
fig/network which are named ifcfg-<configuration-name>.
<configuration-name> is the name of a configuration that should be used
to set up the interface. It may be used to circumvent the automatic
search for a configuration with getcfg. In this case the configuration
names are not restricted. For example if you have a configuration file
ifcfg-my-special you may call ifup my-special <hwdesc>.
PERSISTENT INTERFACE NAMES
There is still a variable PERSISTENT_NAME for ifcfg-* files. But this
should not longer be used. The better way is to make names of inter-
faces persistent immediately after they were registered via udev. Have
a look at /usr/share/doc/packages/sysconfig/README.Persistent_Interâ
face_Names for more information about that. You may disable this by
setting the variable FORCE_PERSISTENT_NAMES in the general config file
/etc/sysconfig/network/config to 'no'.
OPTIONS
The following are options to be specified after the -o switch.
auto Only set up the interface if the configuration has the START-
MODE=auto (or boot, onboot or hotplug.)
[on]boot
Alias for 'auto'.
hotplug
Like auto, but do some extra jobs, because hotplug indicates
that the interface was just (un)registered. These extra jobs
contain (if configured): starting/stopping ifplugd, renaming
interface and removing all status files at ifdown.
manual This is default operation mode and sets up interfaces with
STARTMODE=manual. If option 'rc' is used which implies mode
'auto', you can force mode 'manual'.
rc Special option for the use in rcnetwork (/etc/init.d/network).
See section rcnetwork below.
dhcp Indicates that script is called from dhcp client. When a inter-
face has BOOTPROTO=dhcp ifup/down does not execute any post
action immediately. After dhcp client got a lease and has set
ip address, it calls ifup again, this time with option 'dhcp'.
In this run we finish interface setup.
nodeps If there are interfaces based on this interface, ifdown takes
these depending interfaces down first. If you don't like that,
use 'nodeps'.
prov=<n>
Use provider <n> instead that from config file. Only usefull for
dialup interfaces.
debug Be verbose.
FILES
/sbin/ifup
The script itself.
/etc/sysconfig/network/config
General configuration options. See section GENERAL VARIABLES
below.
/etc/sysconfig/network/ifcfg- <configuration-name>
The files containing the configuration of the devices. An exam-
ple that shows a typical configuration with the name ifcfg-eth0:
IPADDRESS=10.10.11.184
NETMASK=255.255.0.0
BROADCAST=10.10.255.255
STARTMODE=onboot
/etc/sysconfig/network/ifroute- <configuration-name>
You can specify individual routes for every configuration in
these files. See routes (5) for a detailed description.
/etc/sysconfig/network/if-{up,down}.d/
Scripts in these directories will be executed when any interface
is started, if-up.d, and when any interface is stopped, if-
down.d. They have to be executable and may also be binary. The
execution of these programs is controlled by the variables
GLOBAL_POST_UP_EXEC and GLOBAL_PRE_DOWN_EXEC in the network con-
figuration file /etc/sysconfig/network/config These are not
interface specific, and can have any name. If you need inter-
face/configfile specific scripts to be executed have a look at
PRE_UP_SCRIPT, POST_UP_SCRIPT, PRE_DOWN_SCRIPTand
POST_DOWN_SCRIPT.
/etc/sysconfig/network/ifservices- <configuration-name>/
If you don't have a permanent network connection and like that
certain services are not started at boot time unconditionaly but
later after the network connection was established then you can
add these services here. See ifservices (5) for a detailed
description.
/etc/sysconfig/network/ifcfg.template
A template for writing ifcfg-* files.
GENERAL VARIABLES
There are some general settings in the file /etc/sysconfig/network/conâ
fig. If needed you can also set every general variable as an individ-
ual variable in the ifcfg-* files. Please see the description of these
variables in /etc/sysconfig/network/config.
For dhcp there are additional global options in /etc/sysconfig/netâ
work/dhcp. Also these are described there and can be used individually
in ifcfg-* files.
rcnetwork
At boot time network devices are initialized asynchronously via hot-
plug. Once this initialisation process registered an interface for it
this will also trigger a hotplug event which will call ifup. If service
network was still not started ifup will just exit. As soon as service
network is active ifup will do its job and set up the interface. There-
fore the job of the network start script consists of:
- set the 'network active' flag
- set up all interfaces already available
- wait for mandatory interfaces which are still not there
- set up tunnel, vlan, et al.
At boot time the scripts tries to determine the list of mandatory
devices automatically. It considers all interfaces that have a start-
mode 'auto' or are considered as mandatory. Normally it waits 20 sec-
onds for them and exits then with failed is any mandatory interface is
still missing.
Alternatively you may specify all mandatory devices manually in the
variable MANDATORY_DEVICES in the file. /etc/sysconfig/network/config.
There you may also tweak the timeout in WAIT_FOR_INTERFACES.
The network script will only set up devices with with startmodes auto,
onboot or hotplug. To set up an interface with startmode manual you
have to call ifup manually. (rcnetwork calls 'ifup ... -o rc').
DIAGNOSTICS
ifstatus interface
ifup and rcnetwork write status files in /var/run/sysconfig. If some-
thing went completely wrong this files might be interesting.
BUGS
Please report bugs at <http://www.suse.de/feedback>
AUTHOR
Christian Zoz <zoz@suse.de> -- ifup script
Michal Svec <msvec@suse.cz> -- ifup script
Bjoern Jacke -- ifup script
Mads Martin Joergensen <mmj@suse.de> -- ifup manpage
Michal Ludvig <mludvig@suse.cz> -- tunnel support
SEE ALSO
ifcfg(5), routes(5), ifservices(5), ifcfg-wireless(5), ifcfg-tunnel(5),
ifcfg-vlan(5), ifcfg-bonding(5), getcfg(8).
sysconfig August 2004 IFUP(8)
Man(1) output converted with
man2html and wrapped by fishsponge
This page was generated on Tue Feb 13 02:23:10 GMT 2007
|
Man Pages 
