MDNS - Revision history

Unicorn at 13:57, 26 October 2025

2025-10-26T13:57:34Z

← Older revision		Revision as of 13:57, 26 October 2025
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	== Setup avahi2dns ==		== Setup avahi2dns ==

	Name resolution is implemented by musl, and it only supports DNS, so we ~~have~~ to ~~map~~ the avahi results ~~to a~~ regular DNS ~~server~~. This is done by [https://github.com/LouisBrunner/avahi2dns avahi2dns]~~. As of now~~, {{pkg\|avahi2dns}} package ~~is available~~ in the [[Repositories#Testing\|testing]] repository. It can be safely installed by following the [[Repositories#Using_testing_repository\|guidelines]].		Name resolution is implemented by musl, and it only supports DNS, so we need to make the avahi results accessible through regular DNS lookups. This is done by [https://github.com/LouisBrunner/avahi2dns avahi2dns], which is available in the {{pkg\|avahi2dns}} package in the [[Repositories#Testing\|testing]] repository. It can be safely installed after following the [[Repositories#Using_testing_repository\|testing repository setup guidelines]]:

	{{cmd\|$ doas apk add avahi2dns@testing}}		{{cmd\|$ doas apk add avahi2dns@testing}}

	~~since~~ we will want a ~~full~~ DNS server running at port 53, ~~we need to configure~~ avahi2dns to use another port. This is done by default with {{path\|/etc/conf.d/avahi2dns}} containing:		Since we will want a DNS server running locally on port 53, avahi2dns needs to use another port. This is done by default with {{path\|/etc/conf.d/avahi2dns}} containing:

	command_args="-p 5354"		command_args="-p 5354"
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	=== Setup unbound as DNS resolver ===		=== Setup unbound as DNS resolver ===

	We will use [[Setting up unbound DNS server\|unbound]] as the server and {{ic\|resolvconf}} ~~tool~~ to inform unbound about the DHCP results. This option is probably most convenient for a laptop: using the DHCP provided by the server for the regular DNS requests.		We will use [[Setting up unbound DNS server\|unbound]] as the local DNS server and {{ic\|resolvconf}} to inform local applications that a local DNS server exists and to inform unbound about the DHCP results. This option is probably most convenient for a laptop: using the DHCP provided by the server for the regular DNS requests.

	Install the programs: {{cmd\|$ doas apk add {{pkg\|openresolv}} {{pkg\|unbound}}}}		Install the programs: {{cmd\|$ doas apk add {{pkg\|openresolv}} {{pkg\|unbound}}}}

Bezzumnbiu: fix mistakes

2025-06-04T07:20:42Z

fix mistakes

← Older revision		Revision as of 07:20, 4 June 2025
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	=== Using existing bind server as DNS resolver ===		=== Using existing bind server as DNS resolver ===

	It is assumed that a bind(named) server is already installed and running, if not, then you can use the instructions[[Small-Time_DNS_with_BIND9]]		It is assumed that a bind(named) server is already installed and running, if not, then you can use the instructions [[Small-Time_DNS_with_BIND9]]

	Once the bind(named) server is up and running, then the solution is to set an access "zone" for postfix addresses.local		Once the bind(named) server is up and running, then the solution is to set an access "zone" for postfix addresses.local
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	forward only; # rule to use only forwards		forward only; # rule to use only forwards
	forwarders {		forwarders {
	127.0.0.1 port 5354; # Avahi2dns ~~adress~~ and port		127.0.0.1 port 5354; # Avahi2dns address and port
	};		};
	};		};

Prabuanand: fixed wikilinks and rephrased sentence

2025-05-06T10:30:08Z

fixed wikilinks and rephrased sentence

← Older revision		Revision as of 10:30, 6 May 2025
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	command_args="-p 5354"		command_args="-p 5354"

	Enable and start avahi2dns with		Enable and start avahi2dns with the command:{{cmd\|$ doas rc-update add avahi2dns

	{{cmd\|$ doas rc-update add avahi2dns
	$ doas rc-service avahi2dns start}}		$ doas rc-service avahi2dns start}}

	It should now be possible to use DNS to query the address of the printer.		It should now be possible to use DNS to query the address of the printer:{{cmd\|$ drill -p 5354 @127.0.0.1 <printer_name>.local}}

	{{cmd\|$ drill -p 5354 @127.0.0.1 <printer_name>.local}}

	Where printer_name is the hostname given by avahi-browse.		Where printer_name is the hostname given by avahi-browse.
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	== Setup Networkmanager ==		== Setup Networkmanager ==

	If you are already using ~~networkmanager~~, you can leverage {{pkg\|dnsmasq}} as your DNS server which can easily forward mDNS requests to another server.		If you are already using [[NetworkManager\|Networkmanager]], you can leverage {{pkg\|dnsmasq}} as your DNS server which can easily forward mDNS requests to another server.

	Install the {{pkg\|networkmanager-dnsmasq}} package: {{cmd\|$ doas apk add {{pkg\|networkmanager-dnsmasq}}}}		Install the {{pkg\|networkmanager-dnsmasq}} package: {{cmd\|$ doas apk add {{pkg\|networkmanager-dnsmasq}}}}
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	== Without NetworkManager ==		== Without NetworkManager ==

	=== Setup DNS resolver ===		If you are not using [[NetworkManager\|Networkmanager]], you will need to setup a DNS resolver that will forward request of .local domain to avahi2dns and handle other requests normally. There is more than one way to do it.

			=== Setup unbound as DNS resolver ===

	~~If you are not using NetworkManager, you~~ will ~~need to setup a~~ DNS ~~resolver that will forward request of .local domain~~ to ~~avahi2dns and handle other requests normally~~. ~~There is more than one way to do it, but we document an~~ option ~~that~~ is probably most convenient for a laptop: using the DHCP provided server for the regular DNS requests~~. We will use unbound as the server and resolvconf to inform unbound about the DHCP results~~.		We will use [[Setting up unbound DNS server\|unbound]] as the server and {{ic\|resolvconf}} tool to inform unbound about the DHCP results. This option is probably most convenient for a laptop: using the DHCP provided by the server for the regular DNS requests.

	Install the programs: {{cmd\|$ doas apk add {{pkg\|openresolv}} {{pkg\|unbound}}}}		Install the programs: {{cmd\|$ doas apk add {{pkg\|openresolv}} {{pkg\|unbound}}}}
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	This reads the information provided by resolvconf, but forwards .local requests to avahi2dns. We also need to disable dnssec for .local and tell unbound that it is OK to query localhost.		This reads the information provided by resolvconf, but forwards .local requests to avahi2dns. We also need to disable dnssec for .local and tell unbound that it is OK to query localhost.

	Enable and start unbound		Enable and start unbound. {{cmd\|$ doas rc-update add unbound

	{{cmd\|$ doas rc-update add unbound
	$ doas rc-service unbound start}}		$ doas rc-service unbound start}}

	=== Using bind~~(named)~~ as DNS resolver ===		=== Using existing bind server as DNS resolver ===

	It is assumed that bind(named) is already installed and running, if not, then you can use the instructions[[Small-Time_DNS_with_BIND9]]		It is assumed that a bind(named) server is already installed and running, if not, then you can use the instructions[[Small-Time_DNS_with_BIND9]]

	~~If you already have a~~ bind(named) server ~~configured~~, then the solution is to set an access "zone" for postfix addresses.local		Once the bind(named) server is up and running, then the solution is to set an access "zone" for postfix addresses.local

	To do this, add the following lines to the bind configuration file {{path\|/etc/bind/named.conf}} as follows {{Cat\|/etc/bind/named.conf\|		To do this, add the following lines to the bind configuration file {{path\|/etc/bind/named.conf}} as follows {{Cat\|/etc/bind/named.conf\|

Prabuanand: added printer category, fixed wikitags, added note on testing repository for avahi2dns

2025-05-06T10:10:43Z

added printer category, fixed wikitags, added note on testing repository for avahi2dns

Show changes

Prabuanand: moved heading and removed warning

2025-04-22T12:50:42Z

moved heading and removed warning

← Older revision		Revision as of 12:50, 22 April 2025
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	{{DISPLAYTITLE:mDNS}}		{{DISPLAYTITLE:mDNS}}
	[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.		[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.

	{{warning\|There might be in issue in ipv4/ipv6 dual-setups. [https://github.com/LouisBrunner/avahi2dns/issues/21 Check this issue.] [https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/82560 Fixed with this MR.] Note the added --timeout 2.5s.}}

	== Setup avahi ==		== Setup avahi ==
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	NameResolvingService=resolvconf		NameResolvingService=resolvconf

	== ~~Test the setup~~ ==		== Troubleshooting ==

	~~You should now be able to query for both~~ the ~~printer address and regular addresses with~~		=== Test the setup ===

	{{cmd\|drill @127.0.0.1 <printer_name>.local		You should be able to query for both the printer address and regular addresses with: {{cmd\|drill @127.0.0.1 <printer_name>.local
	drill @127.0.0.1 alpinelinux.org}}		drill @127.0.0.1 alpinelinux.org}}

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	Printer discovery should now be working.		Printer discovery should now be working.

			=== Failure in parallel query of A and AAAA requsts ===

			An issue with parallel query of A and AAAA requsts was reported to [https://github.com/LouisBrunner/avahi2dns/issues/21 upstream] related to ipv4/ipv6 dual-setups and since been resolved in Alpine Linux {{MR\|82560}} by adding a timeout 2.5s.

	[[Category:Networking]]		[[Category:Networking]]

Rhizoome at 17:20, 9 April 2025

2025-04-09T17:20:21Z

← Older revision		Revision as of 17:20, 9 April 2025
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	[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.		[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.

	{{warning\|There might be in issue in ipv4/ipv6 dual-setups. [https://github.com/LouisBrunner/avahi2dns/issues/21 Check this issue.] [https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/82560 Fixed with this ~~issue~~.] Note the added --timeout 2.5s.}}		{{warning\|There might be in issue in ipv4/ipv6 dual-setups. [https://github.com/LouisBrunner/avahi2dns/issues/21 Check this issue.] [https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/82560 Fixed with this MR.] Note the added --timeout 2.5s.}}

	== Setup avahi ==		== Setup avahi ==

Rhizoome at 17:20, 9 April 2025

2025-04-09T17:20:07Z

← Older revision		Revision as of 17:20, 9 April 2025
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	[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.		[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.

	{{warning\|There might be in issue in ipv4/ipv6 dual-setups. [https://github.com/LouisBrunner/avahi2dns/issues/21 Check this issue.] [https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/82560 Fixed with this issue.] Note the added --timeout 2.5s.}		{{warning\|There might be in issue in ipv4/ipv6 dual-setups. [https://github.com/LouisBrunner/avahi2dns/issues/21 Check this issue.] [https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/82560 Fixed with this issue.] Note the added --timeout 2.5s.}}

	== Setup avahi ==		== Setup avahi ==

Rhizoome at 17:19, 9 April 2025

2025-04-09T17:19:47Z

← Older revision		Revision as of 17:19, 9 April 2025
Line 2:		Line 2:
	[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.		[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.

	{{warning\|There might be in issue in ipv4/ipv6 dual-setups. [https://github.com/LouisBrunner/avahi2dns/issues/21 Check this issue.]}}		{{warning\|There might be in issue in ipv4/ipv6 dual-setups. [https://github.com/LouisBrunner/avahi2dns/issues/21 Check this issue.] [https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/82560 Fixed with this issue.] Note the added --timeout 2.5s.}

	== Setup avahi ==		== Setup avahi ==

Rhizoome at 16:31, 3 April 2025

2025-04-03T16:31:32Z

← Older revision		Revision as of 16:31, 3 April 2025
Line 2:		Line 2:
	[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.		[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.

	{{warning\|~~The~~ might be in issue in ipv4/ipv6 dual-setups. [https://github.com/LouisBrunner/avahi2dns/issues/21 Check this issue.]}}		{{warning\|There might be in issue in ipv4/ipv6 dual-setups. [https://github.com/LouisBrunner/avahi2dns/issues/21 Check this issue.]}}

	== Setup avahi ==		== Setup avahi ==

Rhizoome at 16:31, 3 April 2025

2025-04-03T16:31:23Z

← Older revision		Revision as of 16:31, 3 April 2025
Line 1:		Line 1:
	{{DISPLAYTITLE:mDNS}}		{{DISPLAYTITLE:mDNS}}
	[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.		[https://en.wikipedia.org/wiki/Multicast_DNS Multicast DNS] is a protocol that is normally used for the discovery of printers. Avahi is a popular implementation by but more setup is needed for the regular name resolution to see the results.

			{{warning\|The might be in issue in ipv4/ipv6 dual-setups. [https://github.com/LouisBrunner/avahi2dns/issues/21 Check this issue.]}}

	== Setup avahi ==		== Setup avahi ==