- "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)."
- 1 Installation
- 2 Using Avahi
- 2.1 Obtaining IPv4LL IP address
- 2.2 Hostname resolution
- 2.3 File sharing
- 2.4 Link-Local (Bonjour/Zeroconf) chat
- 2.5 Airprint from Mobile Devices
- 2.6 Firewall
- 2.7 Customizing Avahi
- 3 See also
You can manage the Avahi daemon with
avahi-daemon.service using systemd.
For some reason, Avahi comes with IPv6 disabled by default. To enable it, set
Obtaining IPv4LL IP address
By default, if you are getting IP using DHCP, you are using thepackage. 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:
... #noipv4ll ...
# avahi-autoipd -D
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
Additional info about mdns
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
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
Avahi includes several utilities which help you discover the services running on a network. For example, run
to discover services in your network.
The Avahi Zeroconf Browser (
avahi-discover – note that it needs avahi's optional dependencies and ) shows the various services on your network. You can also browse SSH and VNC Servers using
There's a good list of software with Avahi support at their website: http://avahi.org/wiki/Avah4users
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"> <service-group> <name replace-wildcards="yes">NFS Music Share on %h</name> <service> <type>_nfs._tcp</type> <port>2049</port> <txt-record>path=/data/shared/Music</txt-record> </service> </service-group>
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 Arch User Repository and have shared files between the LAN, with no configuration, no hours in samba hacking, no nothing - it just works.AUR from the
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"> <service-group> <name>FTP file sharing</name> <service> <type>_ftp._tcp</type> <port>21</port> </service> </service-group>
When you are done, restart the
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 theAUR.
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"> <service-group> <name>yourPrnterName</name> <service> <type>_ipp._tcp</type> <subtype>_universal._sub._ipp._tcp</subtype> <port>631</port> <txt-record>txtver=1</txt-record> <txt-record>qtotal=1</txt-record> <txt-record>rp=printers/yourPrnterName</txt-record> <txt-record>ty=yourPrnterName</txt-record> <txt-record>adminurl=http://22.214.171.124:631/printers/yourPrnterName</txt-record> <txt-record>note=Office Laserjet 4100n</txt-record> <txt-record>priority=0</txt-record> <txt-record>product=(GPL Ghostscript)</txt-record> <txt-record>printer-state=3</txt-record> <txt-record>printer-type=0x801046</txt-record> <txt-record>Transparent=T</txt-record> <txt-record>Binary=T</txt-record> <txt-record>Fax=F</txt-record> <txt-record>Color=T</txt-record> <txt-record>Duplex=T</txt-record> <txt-record>Staple=F</txt-record> <txt-record>Copies=T</txt-record> <txt-record>Collate=F</txt-record> <txt-record>Punch=F</txt-record> <txt-record>Bind=F</txt-record> <txt-record>Sort=F</txt-record> <txt-record>Scan=F</txt-record> <txt-record>pdl=application/octet-stream,application/pdf,application/postscript,image/jpeg,image/png,image/urf</txt-record> <txt-record>URF=W8,SRGB24,CP1,RS600</txt-record> </service> </service-group>
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
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
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
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.
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 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 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 --> <service-group> <name replace-wildcards="yes">%h</name> <service> <type>_qotd._tcp</type> <port>17</port> </service> </service-group>
For more complicated scenarios, such as advertising services running on a different server, DNS sub-types and so on, consult
Modifying the service-types database
As noted above, avahi comes with tools to browse advertised services. Both
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
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:
#!/bin/bash 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.
$./whatever_you_named_the_script.sh $ 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 $ls 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 gdbmtool>quit
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