ifplugd(8)
NAME
ifplugd - A link detection daemon for ethernet devices
SYNOPSIS
ifplugd [options]
DESCRIPTION
ifplugd is a daemon which will automatically configure your ethernet device when a cable is plugged in and automatically unconfigure it if the cable is pulled. This is useful on laptops with on-board network adapters, since it will only configure the interface when a cable is really connected. It uses your distribution's native ifup/ifdown programs, but can be configured to do anything you wish when the state of the interface changes. It may ignore short unplugged whiles (-d option) or plugged whiles (-u option). ifplugd may be used in "compatibility mode" by specifying -F on the command line. Than ifplugd will treat network drivers which do not support link beat querying as always online.
OPTIONS
-a | --no-auto
Do not enable interface automatically (default: off)
-n | --no-daemon
Do not daemonize (for debugging) (default: off)
-s | --no-syslog
Do not use syslog, use stdout instead (for debugging) (default:
off).
-b | --no-beep
Do not beep (off), overrides --no-beep-up and --no-beep-down.
-U | --no-beep-up
Do not beep on interface up (off)
-D | --no-beep-down
Do not beep on interface down (off)
-f | --ignore-fail
Ignore detection failure, retry instead. Failure is treated as
"no link". (default: off)
-F | --ignore-fail-positive
Ignore detection failure, retry instead. Failure is treated as
"link detected". (default: off)
-i | --iface= IFACE
Specify ethernet interface (default: eth0)
-r | --run= EXEC
Specify program to execute when link status changes (default:
/etc/ifplugd/ifplugd.action)
-I | --ignore-retval
Don't exit on nonzero return value of program executed on link
change. (default: off)
-t | --poll-time= SECS
Specify poll time in seconds (default: 1)
-T | --poll-utime= USECS
Specify poll time in microseconds, added to -t (default: 0)
-u | --delay-up= SECS
Specify delay for configuring interface (default: 0)
-d | --delay-down= SECS
Specify delay for deconfiguring interface (default: 5)
-m | --api-mode= MODE
Force a specific link beat detection ioctl() API. Possible
values are auto, iff, wlan, ethtool, mii, and priv for automatic
detection, interface flag (IFF_RUNNING), wireless extension,
SIOCETHTOOL, SIOCGMIIREG resp. SIOCPRIV. Only the first
character of the argument is relevant, case insensitive.
(default: auto)
-p | --no-startup
Don't call the script to bring up network on deamon start
(default: off)
-q | --no-shutdown
Don't call the script for network shutdown on deamon quit
(default: off)
-w | --wait-on-fork
When daemonizing, wait until the background process finished
with the initial link beat detection. When this is enabled, the
parent process will return the link status on exit. 2 means link
beat detected, 3 stands for link beat not detected, everything
else is an error.
-W | --wait-on-kill
When killing a running daemon (with -k) wait until the daemon
died.
-x | --extra-arg= ARG
Specify an extra argument to be passed to the action script.
-M | --monitor
Don't fail when the network interface is not available, instead
use NETLINK to monitor device avaibility. The is useful for
PCMCIA devices and similar.
-h | --help
Show help
-k | --kill
Kill a running daemon (Specify -i to select the daemon instance
to kill)
-c | --check-running
Check if a daemon is running for a given network interface. Sets
the return value to 0 if a daemon is already running or to 255
if not.
-v | --version
Show version
-S | --supend
Suspend a running daemon. The daemon will no longer check the
link status until it is resumed (-R) again. (Specify -i to
select the daemon instance to suspend.)
-R | --resume
Resume a suspended daemon. (Specify -i to select the daemon
instance to resume.)
-z | --info
Request that a running daemon shall write its status information
to syslog. (Specify -i to select the daemon instance to send the
request to.)
FILES
/etc/default/ifplugd: this file is sourced by the init script /etc/init.d/ifplugd and contains the interface to be monitored and the options to be used. /etc/ifplugd/ifplugd.action: this is the script which will be called by the daemon whenever the state of the interface changes. It takes two areguments: the first is the interface name (eg. eth0), the second either "up" or "down". /var/run/ifplugd.<iface>.pid: the pid file for ifplugd.
ENVIRONMENT
The action script will be called with two environment variables set: IFPLUGD_PREVIOUS The previous link status. Either "up", "down", "error" or "disabled". The former values should be obvious, the latter is set on daemon startup. IFPLUGD_CURRENT The current link status. See above for possible values.
SIGNALS
SIGINT, SIGTERM ifplugd will quit, possibly running the shutdown script. This is issued by passing -k to ifplugd. SIGQUIT ifplugd will quit, the shutdown script is never run. SIGHUP ifplugd will write its status information to syslog. This is issued by -z. SIGUSR1 ifplugd will go to suspend mode. (-S) SIGUSR2 ifplugd will resume from suspend mode. (-R)
AUTHOR
ifplugd was written by Lennart Poettering <mzvscyhtq (at) 0pointer (dot) de>. ifplugd is available at http://0pointer.de/lennart/projects/ifplugd/
SEE ALSO
ifplugd.conf(5), ifup(8), interfaces(5), ifconfig(8), ifplugstatus(8)
COMMENTS
This man page was written using xmltoman(1) by Oliver Kurth.
Opportunity
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
Free Books
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Education
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.
