1avahi-daemon.conf(5)          File Formats Manual         avahi-daemon.conf(5)
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NAME

6       avahi-daemon.conf - avahi-daemon configuration file
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SYNOPSIS

9       /etc/avahi/avahi-daemon.conf
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DESCRIPTION

12       avahi-daemon.conf is the configuration file for avahi-daemon.
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SECTION [SERVER]

15       host-name= Set the host name avahi-daemon tries to register on the LAN.
16       If omited defaults to the system host name as  set  with  the  sethost‐
17       name() system call.
18
19       host-name-from-machine-id=  Takes  a  boolean value ("yes" or "no"). If
20       set to "yes" avahi-daemon will use the machine-id as name on the LAN.
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22       domain-name= Set the default domain name avahi-daemon tries to register
23       its  host  name  and  services  on  the  LAN in. If omitted defaults to
24       ".local".
25
26       browse-domains= Set a comma separated  list  of  browsing  domains  (in
27       addition  to  the  default  one  and those announced inside the default
28       browsing domain). Please note that  the  user  may  specify  additional
29       browsing    domains   on   the   client   side,   either   by   setting
30       $AVAHI_BROWSE_DOMAINS to a list of colon separated domains or by adding
31       them  to  the XDG config file ~/.config/avahi/browse-domains (separated
32       by newlines).
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34       use-ipv4= Takes a boolean value ("yes" or "no"). If set to "no"  avahi-
35       daemon will not use IPv4 sockets. Default is "yes".
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37       use-ipv6=  Takes a boolean value ("yes" or "no"). If set to "no" avahi-
38       daemon will not use IPv6 sockets. Default is "yes".
39
40       allow-interfaces= Set a comma separated list of allowed network  inter‐
41       faces  that should be used by the avahi-daemon. Traffic on other inter‐
42       faces will be ignored. If set to an empty  list  all  local  interfaces
43       except loopback and point-to-point will be used.
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45       deny-interfaces=  Set a comma separated list of network interfaces that
46       should be ignored by avahi-daemon. Other not specified interfaces  will
47       be  used, unless allow-interfaces= is set. This option takes precedence
48       over allow-interfaces=.
49
50       check-response-ttl= Takes a boolean value ("yes" or "no").  If  set  to
51       "yes",  an  additional security check is activated: incoming IP packets
52       will be ignored unless the IP TTL is 255. Earlier  mDNS  specifications
53       required  this check. Since this feature may be incompatible with newer
54       implementations of mDNS it defaults to "no". On the other hand it  pro‐
55       vides extra security.
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57       use-iff-running= Takes a boolean value ("yes" or "no"). If set to "yes"
58       avahi-daemon monitors the IFF_RUNNING flag bit which is  used  by  some
59       (modern)  network  drivers  to  tell  user  space if a network cable is
60       plugged in (in case of copper ethernet), or the network card is associ‐
61       ated with some kind of network (in case of WLAN). If IFF_RUNNING is set
62       avahi-daemon will automatically announce its services on that  network.
63       Unfortunately  far too many network drivers do not support this flag or
64       support it in a broken way. Therefore this option defaults to "no".
65
66       enable-dbus= Takes either "yes", "no" or "warn". If set to "yes" avahi-
67       daemon connects to D-Bus, offering an object oriented client API. It is
68       only available if Avahi has been compiled with --enable-dbus  in  which
69       case  it  defaults  to "yes". "warn" behaves like "yes", but the daemon
70       starts up even when it fails to connect to a D-Bus daemon. In addition,
71       if  the  connection  to the D-Bus daemon is terminated we try to recon‐
72       nect. (Unless we are in a chroot() environment  where  this  definitely
73       will fail.)
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75       disallow-other-stacks= Takes a boolean value ("yes" or "no"). If set to
76       "yes" no other process is allowed to bind to UDP port 5353. This effec‐
77       tively  impedes other mDNS stacks from running on the host. Use this as
78       a security measure to make sure that only Avahi is responsible for mDNS
79       traffic.  Please  note  that  we do not recommend running multiple mDNS
80       stacks on the same host simultaneously. This hampers reliability and is
81       a waste of resources. However, to not annoy people this option defaults
82       to "no".
83
84       allow-point-to-point= Takes a boolean value ("yes" or "no"). If set  to
85       "yes"  avahi-daemon  will  make  use of interfaces with the POINTOPOINT
86       flag set. This option defaults to "no" as it might make mDNS unreliable
87       due  to  usually  large latencies with such links and opens a potential
88       security hole by allowing mDNS access from  Internet  connections.  Use
89       with care and YMMV!
90
91       cache-entries-max=  Takes  an  unsigned  integer  specifying  how  many
92       resource records are cached per interface.  Bigger  values  allow  mDNS
93       work correctly in large LANs but also increase memory consumption.
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95       clients-max=  Takes  an unsigned integer. The maximum number of concur‐
96       rent D-Bus clients allowed. If the maximum number  is  reached  further
97       clients will be refused until at least one existing client disconnects.
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99       objects-per-client-max=  Takes  an unsigned integer. The maximum number
100       of objects (entry groups, browsers, resolvers) that may  be  registered
101       per  D-Bus  client  at a time. If the maximum number is reached further
102       object creation will be refused until at least one object is freed.
103
104       entries-per-entry-group-max= Takes an  unsigned  integer.  The  maximum
105       number of entries (resource records) per entry group registered by a D-
106       Bus client at a time. If the maximum number is reached further resource
107       records may not be added to an entry group.
108
109       ratelimit-interval-usec= Takes an unsigned integer. Sets the per-inter‐
110       face packet rate-limiting interval parameter. Together with  ratelimit-
111       burst=  this may be used to control the maximum number of packets Avahi
112       will generated in a specific period of time on an interface.
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114       ratelimit-burst= Takes an  unsigned  integer.  Sets  the  per-interface
115       packet rate-limiting burst parameter. Together with ratelimit-interval-
116       usec= this may be used to control the maximum number of  packets  Avahi
117       will generated in a specific period of time on an interface.
118

SECTION [WIDE-AREA]

120       enable-wide-area=  Takes  a boolean value ("yes" or "no"). Enable wide-
121       area DNS-SD, aka DNS-SD over unicast  DNS.  If  this  is  enabled  only
122       domains  ending  in  .local will be resolved on mDNS, all other domains
123       are resolved via unicast DNS. If you want to maintain multiple  differ‐
124       ent  multicast  DNS  domains even with this option enabled we encourage
125       you to use subdomains of .local, such as "kitchen.local".  This  option
126       defaults to "yes".
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SECTION [PUBLISH]

129       disable-publishing=  Takes  a  boolean value ("yes" or "no"). If set to
130       "yes", no record will be published by Avahi, not even  address  records
131       for  the local host. Avahi will be started in a querying-only mode. Use
132       this is a security measure. This option defaults to "no"
133
134       disable-user-service-publishing= Takes a boolean value ("yes" or "no").
135       If  set to "yes", Avahi will still publish address records and suchlike
136       but will not allow user applications to publish services. Use this is a
137       security measure. This option defaults to "no"
138
139       add-service-cookie=  Takes  a  boolean value ("yes" or "no"). If set to
140       "yes" an implicit TXT entry will be added  to  all  locally  registered
141       services,  containing a cookie value which is chosen randomly on daemon
142       startup. This can be used to detect if two services  on  two  different
143       interfaces/protocols are actually identical. Defaults to "no".
144
145       publish-addresses=  Takes  a  boolean  value ("yes" or "no"). If set to
146       "yes" avahi-daemon will register mDNS address records for all local  IP
147       addresses. Unless you want to use avahi-daemon exclusively for browsing
148       it's recommended to enable this. If you plan to register local services
149       you need to enable this option. Defaults to "yes".
150
151       publish-hinfo=  Takes  a boolean value ("yes" or "no"). If set to "yes"
152       avahi-daemon will register an mDNS HINFO record on all interfaces which
153       contains  information  about  the local operating system and CPU, which
154       might be useful for administrative purposes. This is recommended by the
155       mDNS  specification but not required. For the sake of privacy you might
156       choose to disable this feature. Defaults to "no".
157
158       publish-workstation= Takes a boolean value ("yes" or "no"). If  set  to
159       "yes"  avahi-daemon will register a service of type "_workstation._tcp"
160       on the local LAN. This might  be  useful  for  administrative  purposes
161       (i.e.  browse  for  all  PCs on the LAN), but is not required or recom‐
162       mended by any specification. Newer MacOS X releases register a  service
163       of this type. Defaults to "no".
164
165       publish-domain=  Takes a boolean value ("yes" or "no"). If set to "yes"
166       avahi-daemon will announce the locally used domain name (see above) for
167       browsing by other hosts. Defaults to "yes".
168
169       publish-dns-servers=  Takes  a comma separated list of IP addresses for
170       unicast DNS servers. You can use this to announce unicast  DNS  servers
171       via  mDNS.  When  used in conjunction with avahi-dnsconfd on the client
172       side this allows DHCP-like configuration of unicast DNS servers.
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174       publish-resolv-conf-dns-servers= Takes a boolean value ("yes" or "no").
175       If set to "yes" avahi-daemon will publish the unicast DNS servers spec‐
176       ified in /etc/resolv.conf in addition to those specified with  publish-
177       dns-servers.  Send  avahi-daemon  a SIGHUP to have it reload this file.
178       Defaults to "no".
179
180       publish-aaaa-on-ipv4= Takes a boolean value ("yes" or "no"). If set  to
181       "yes"  avahi-daemon will publish an IPv6 AAAA record via IPv4, i.e. the
182       local IPv6 addresses can be resolved using an IPv4 transport. Only use‐
183       ful when IPv4 is enabled with use-ipv4=true. Defaults to "yes".
184
185       publish-a-on-ipv6=  Takes  a  boolean  value ("yes" or "no"). If set to
186       "yes" avahi-daemon will publish an IPv4 A record  via  IPv6,  i.e.  the
187       local IPv4 addresses can be resolved using an IPv6 transport. Only use‐
188       ful when IPv6 is enabled with use-ipv6=true. Defaults to "no".
189

SECTION [REFLECTOR]

191       enable-reflector= Takes a boolean value ("yes"  or  "no").  If  set  to
192       "yes"  avahi-daemon  will  reflect  incoming mDNS requests to all local
193       network interfaces, effectively allowing clients to browse  mDNS/DNS-SD
194       services on all networks connected to the gateway. The gateway is some‐
195       what intelligent and should work with all kinds of mDNS traffic, though
196       some  functionality  is lost (specifically the unicast reply bit, which
197       is used rarely anyway).  Make  sure  to  not  run  multiple  reflectors
198       between the same networks, this might cause them to play Ping Pong with
199       mDNS packets. Defaults to "no".
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201       reflect-ipv= Takes a boolean value ("yes" or "no"). If set to "yes" and
202       enable-reflector  is  enabled,  avahi-daemon  will forward mDNS traffic
203       between IPv4 and IPv6, which is usually not  recommended.  Defaults  to
204       "no".
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SECTION [RLIMITS]

207       This  section  is used to define system resource limits for the daemon.
208       See setrlimit(2) for more information. If any of  the  options  is  not
209       specified  in  the  configuration file, avahi-daemon does not change it
210       from the system defaults.
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212       rlimit-as= Value in bytes for RLIMIT_AS (maximum size of the  process's
213       virtual memory). Sensible values are heavily system dependent.
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215       rlimit-core=  Value  in bytes for RLIMIT_CORE (maximum core file size).
216       Unless you want to debug avahi-daemon, it is safe to set this to 0.
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218       rlimit-data= Value in  bytes  for  RLIMIT_DATA  (maximum  size  of  the
219       process's data segment). Sensible values are heavily system dependent.
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221       rlimit-fsize= Value for RLIMIT_FSIZE (maximum size of files the process
222       may create). Since avahi-daemon shouldn't write any files to  disk,  it
223       is safe to set this to 0.
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225       rlimit-nofile=  Value for RLIMIT_NOFILE (open file descriptors). avahi-
226       daemon shouldn't need more than 15 to 20 open file descriptors  concur‐
227       rently.
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229       rlimit-stack=  Value  in  bytes  for  RLIMIT_STACK (maximum size of the
230       process stack). Sensible values are heavily system dependent.
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232       rlimit-nproc= Value for RLIMIT_NPROC (max number of  processes  a  user
233       can  launch).  avahi-daemon  forks of a helper process on systems where
234       chroot(2) is available therefore this value should not be set below  2.
235       Note  that  while  the  process limit only applies to this process, the
236       total count of processes to reach that limit includes all processes  on
237       the  system  with  the  same  UID, including any containers without UID
238       remapping (such as lxd containers with  security.privileged=true).  The
239       default configuration of 3 was removed to prevent problems in this sce‐
240       nario.
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AUTHORS

243       The Avahi Developers <avahi (at) lists (dot)  freedesktop  (dot)  org>;
244       Avahi is available from http://avahi.org/
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SEE ALSO

247       avahi-daemon(8), avahi-dnsconfd(8)
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COMMENTS

250       This man page was written using xml2man(1) by Oliver Kurth.
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