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From Wikipedia:Avahi (software):

"Avahi is a free Zero-configuration networking (zeroconf) implementation, including a system for multicast DNS/DNS-SD service discovery. It allows programs to publish and discover services and hosts running on a local network with no specific configuration. For example you can plug into a network and instantly find printers to print to, files to look at and people to talk to. It is licensed under the GNU Lesser General Public License (LGPL)."


Install avahi from the official repositories.

You can manage the Avahi daemon with avahi-daemon.service using systemd.

Enable IPv6

For some reason, Avahi comes with IPv6 disabled by default. To enable it, set use-ipv6 to yes in /etc/avahi/avahi-daemon.conf.

Using Avahi

Obtaining IPv4LL IP address

Merge-arrows-2.pngThis article or section is a candidate for merging with dhcpcd.Merge-arrows-2.png

Notes: should be merged into the main page (Discuss in Talk:Avahi#)

By default, if you are getting IP using DHCP, you are using the dhcpcd package. It can attempt to obtain an IPv4LL address if it failed to get one via DHCP. By default this option is disabled. To enable it, comment noipv4ll string:


Alternatively, run avahi-autoipd:

# avahi-autoipd -D

Hostname resolution

Note: Using Avahi for IPv6 hostname resolution is severly limited and not really usable.[1] (summary: you cannot do something trivial as ping6 archy.local)

Avahi also allows you to access computers using their hostnames. However by default, .local querying is disabled in Arch Linux. To enable support for .local, edit the file /etc/nsswitch.conf and change the line:

hosts: files dns myhostname


hosts: files mdns_minimal [NOTFOUND=return] dns myhostname

Install the nss-mdns package and start avahi-daemon.service, for each host.

Additional info about mdns

The mdns_minimal module handles queries for the .local TLD only. Note the [NOTFOUND=return], which specifies that if mdns_minimal cannot find *.local, it will not continue to search for it in dns, myhostname, etc. In case you have configured Avahi to use a different TLD, you should replace mdns_minimal [NOTFOUND=return] with the full mdns module. There also are IPv4-only and IPv6-only modules mdns[46](_minimal).


Avahi includes several utilities which help you discover the services running on a network. For example, run

avahi-browse -alr

to discover services in your network.

The Avahi Zeroconf Browser (avahi-discover – note that it needs avahi's optional dependencies pygtk and python2-dbus) shows the various services on your network. You can also browse SSH and VNC Servers using bssh and bvnc respectively.

There's a good list of software with Avahi support at their website: http://avahi.org/wiki/Avah4users

File sharing


If you have an NFS share set up, you can use Avahi to be able to automount them in Zeroconf-enabled browsers (such as Konqueror on KDE and Finder on OS X). Create a .service file in /etc/avahi/services with the following contents:

<?xml version="1.0" standalone='no'?>
<!DOCTYPE service-group SYSTEM "avahi-service.dtd">
  <name replace-wildcards="yes">NFS Music Share on %h</name>

The port is correct if you have insecure as an option in your /etc/exports; otherwise, it needs to be changed (note that insecure is needed for OS X clients). The path is the path to your export, or a subdirectory of it. For some reason the automount functionality has been removed from Leopard, however a script is available. This was based upon this post.


Should work out-of-the-box.


You can grab gshareAUR from the Arch User Repository and have shared files between the LAN, with no configuration, no hours in samba hacking, no nothing - it just works.


Sourced from ubuntuforums.org. If you would rather use a regular ftp service, install vsftpd and avahi. Change the settings of vsftpd according to what is shown on the ubuntuforums page or according to your own personal preferences (See 'man vsftpd.conf).

Create a ftp.service file in /etc/avahi/services and paste in that file

<?xml version="1.0" standalone='no'?>
   <!DOCTYPE service-group SYSTEM "avahi-service.dtd">
   <name>FTP file sharing</name>

When you are done, restart the avahi-daemon.service and vsftpd.service services.

After that you should be able to browse through the ftp server from another computer in your network. The steps shown in this section are created so that the ftp server is 'advertised' by avahi to the local Zeroconf network.

Unless you are using GNOME or KDE, you might not be able to log in to the ftp server directly through your file manager, and so you will have to use a ftp client pointed to the IP address of the server or the hostname of the machine (as shown in this section).


Giver is a mono program that allows simple file-sharing between two desktops when both are running Giver. All you need to do is click and drag the file to the name or picture of the person you wish to send the file to.

A package is on the giverAUR.

Note that this depends on gnome-sharp, which has heavy GNOME dependencies.

Link-Local (Bonjour/Zeroconf) chat

Avahi can be used for bonjour protocol support under linux. Check Wikipedia:Comparison of instant messaging clients or List of applications#Instant messaging for a list of clients supporting the bonjour protocol.

Airprint from Mobile Devices

Avahi along with CUPS also provides the capability to print to just about any printer from airprint compatible mobile devices. In order to enable print capability from your device, simply create an avahi service file for your printer in /etc/avahi/services and restart avahi. An example of a generic services file for an HP-Laserjet printer would be similar to the following with the name, rp, ty, adminurl and note fields changed. Save the file as /etc/avahi/services/youFileName.service:

<?xml version="1.0" standalone='no'?><!--*-nxml-*-->
<!DOCTYPE service-group SYSTEM "avahi-service.dtd">
    <txt-record>note=Office Laserjet 4100n</txt-record>
    <txt-record>product=(GPL Ghostscript)</txt-record>

Alternatively, https://raw.github.com/tjfontaine/airprint-generate/master/airprint-generate.py can be used to generate Avahi service files. It depends on python2 and pycups. The script can be run using:

# python2 airprint-generate.py -d /etc/avahi/services
Note: If your printer under http://localhost:631/printers is "Not Shared", this python script won't output any file to /etc/avahi/services; in that case, you'll need to "Modify Printer" under one of the CUPS drop-down menus to turn sharing on. If that doesn't work, check out the ArchWiki on CUPS printer sharing.


Be sure to open UDP port 5353 if you're using iptables:

 # iptables -A INPUT -p udp -m udp --dport 5353 -j ACCEPT

If you're following the more-than-useful Simple stateful firewall format for your firewall:

 # iptables -A UDP -p udp -m udp --dport 5353 -j ACCEPT

Customizing Avahi

Adding Services

Avahi advertises the services whose *.service files are found in /etc/avahi/services. If you want to advertise a service for which there is no *.service file, it is very easy to create your own.

As an example, let's say you wanted to advertise a quote of the day (QOTD) service operating per RFC865 on TCP port 17 which you are running on your machine

The first thing to do is to determine the <type>. man avahi.service indicates that the type should be "the DNS-SD service type for this service. e.g. '_http._tcp'". Since the DNS-SD register was merged into the IANA register in 2010, we look for the service name on the IANA register or in /etc/services file. The service name shown there is qotd. Since we're running QOTD on tcp, we now know the service is _qotd._tcp and the port (per IANA and RFC865) is 17.

Our qotd.service file is thus:

<?xml version="1.0" standalone='no'?><!--*-nxml-*-->
<!DOCTYPE service-group SYSTEM "avahi-service.dtd">

  This file is part of avahi.

  avahi is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as
  published by the Free Software Foundation; either version 2 of the
  License, or (at your option) any later version.

  avahi is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with avahi; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  02111-1307 USA.

<!-- See avahi.service(5) for more information about this configuration file -->


  <name replace-wildcards="yes">%h</name>



For more complicated scenarios, such as advertising services running on a different server, DNS sub-types and so on, consult man avahi.service.

Modifying the service-types database

As noted above, avahi comes with tools to browse advertised services. Both avahi-browse and avahi-discover use a database file to furnish descriptions of the relevant service. That database contains the names of many, but not all, services.

Sadly, it doesn't contain the QOTD service we just created. Thus avahi-browse -a would show the following ugly entry

+ wlp2s0 IPv4 MyServer                                        _qotd._tcp local
Getting the Sources

First, download the files build-db.in and service-types files from the service-type-database subdirectory in the the avahi github mirror to a build directory.

wget https://raw.githubusercontent.com/Distrotech/avahi/distrotech-avahi/service-type-database/build-db.in
wget https://raw.githubusercontent.com/Distrotech/avahi/distrotech-avahi/service-type-database/service-types
Modify the Sources

Second, create the following script:

sed -e 's,@PYTHON\@,/usr/bin/python2.7,g' \
    -e 's,@DBM\@,gdbm,g' < build-db.in > build-db
chmod +x build-db

This mimics what the Makefile would do if one were building all of avahi. It creates a file named build-b.

$ ls
build-db build-db.in service-types whatever_you_named_the_script.sh

Third, make the changes needed to add your new QOTD service to the service-types file. This file has one entry per line, with the entries in the format type:Human Readable Description. Note that the human readable description can contain spaces.

In our example, we add the following entry to the end of the file:

_qotd._tcp:Quote of the Day (QOTD) Server
Build and Install the New Database

Now run the build-db python script (be sure to use python2 not python3). This will build the service-types.db file. Check to make sure it's been built and use gdbmtools to make sure the new database is loadable and contains the new entry:

$/usr/bin/python2.7 build-db
build-db build-db.in service-types service-types.db whatever_you_named_the_script.sh
$gdbmtool service-types.db

Welcome to the gdbm tool.  Type ? for help.

gdbmtool>fetch _qotd._tcp
Quote of the Day (QOTD) Server

Now copy the old database to a backup location, move the new database to the live directory and use avahi-browse database dump command to make sure avahi sees the new entry:

$cp /usr/lib/avahi/service-types.db /backup-directory
$sudo cp /build-directory/service-types.db /usr/lib/avahi/service-types.db
$avahi-browse -b | grep QOTD
Quote of the Day (QOTD) Server

The entry in avahi-browse should now be:

+ wlp2s0 IPv4 MyServer                                        Quote of the Day (QOTD) Server local

See also