From: Zbigniew Jędrzejewski-Szmek Date: Tue, 2 Jun 2020 16:21:04 +0000 (+0200) Subject: man: rework description of Domains= X-Git-Tag: v246-rc1~129^2~4 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=801d25ef0f117e283e9bacabb9eb96cdbbab5de0;p=thirdparty%2Fsystemd.git man: rework description of Domains= We said that ~domains "do not define a search path", which is mighty confusing, because this is exactly what they do. So let's try to make this a bit easier for the reader: start by saying that there are two things going on here, and describe each one from user's POV. --- diff --git a/man/resolved.conf.xml b/man/resolved.conf.xml index 9be41baaa5a..33265f755cb 100644 --- a/man/resolved.conf.xml +++ b/man/resolved.conf.xml @@ -67,20 +67,28 @@ Domains= - A space-separated list of domains. These domains are used as search suffixes when resolving - single-label hostnames (domain names which contain no dot), in order to qualify them into fully-qualified - domain names (FQDNs). Search domains are strictly processed in the order they are specified, until the name - with the suffix appended is found. For compatibility reasons, if this setting is not specified, the search - domains listed in /etc/resolv.conf are used instead, if that file exists and any domains - are configured in it. This setting defaults to the empty list. - - Specified domain names may optionally be prefixed with ~. In this case they do not - define a search path, but preferably direct DNS queries for the indicated domains to the DNS servers configured - with the system DNS= setting (see above), in case additional, suitable per-link DNS servers - are known. If no per-link DNS servers are known using the ~ syntax has no effect. Use the - construct ~. (which is composed of ~ to indicate a routing domain and - . to indicate the DNS root domain that is the implied suffix of all DNS domains) to use the - system DNS server defined with DNS= preferably for all domains. + A space-separated list of domains optionally prefixed with ~, + used for two distinct purposes described below. Defaults to the empty list. + + Any domains not prefixed with ~ are used as search + suffixes when resolving single-label hostnames (domain names which contain no dot), in order to + qualify them into fully-qualified domain names (FQDNs). These "search domains" are strictly processed + in the order they are specified in, until the name with the suffix appended is found. For + compatibility reasons, if this setting is not specified, the search domains listed in + /etc/resolv.conf with the search keyword are used instead, if + that file exists and any domains are configured in it. + + The domains prefixed with ~ are called "routing domains". All domains listed + here (both search domains and routing domains after removing the ~ prefix) define + a search path that preferably directs DNS queries to this inteface. This search path has an effect + only when suitable per-link DNS servers are known. Such servers may be defined through the + DNS= setting (see above) and dynamically at run time, for example from DHCP + leases. If no per-link DNS servers are known, routing domains have no effect. + + Use the construct ~. (which is composed from ~ to + indicate a routing domain and . to indicate the DNS root domain that is the + implied suffix of all DNS domains) to use the DNS servers defined for this link preferably for all + domains.