diff --git a/man/systemd-resolved.service.xml b/man/systemd-resolved.service.xml
index 3d7bb52d66..d7334e01ec 100644
--- a/man/systemd-resolved.service.xml
+++ b/man/systemd-resolved.service.xml
@@ -143,16 +143,45 @@
lookup zones on all matching interfaces). If the lookup failed on
all interfaces, the last failing response is returned.
- Routing of lookups may be influenced by configuring
- per-interface domain names. See
- systemd.network5
- for details. Lookups for a hostname ending in one of the
- per-interface domains are exclusively routed to the matching
- interfaces.
+ Routing of lookups may be influenced by configuring per-interface domain names and other settings. See
+ systemd.network5 and
+ resolvectl1 for details. The
+ following query routing logic applies for unicast DNS traffic:
+
+
+ If a name to look up matches (that is: is equal to or has as suffix) any of the configured search
+ or route-only domains of any link (or the globally configured DNS settings), the "best matching"
+ search/route-only domain is determined: the matching one with the most labels. The query is then sent to all DNS
+ servers of any links or the globally configured DNS servers associated with this "best matching"
+ search/route-only domain. (Note that more than one link might have this same "best matching" search/route-only
+ domain configured, in which case the query is sent to all of them in parallel).
+
+ If a query does not match any configured search/route-only domain (neither per-link nor global),
+ it is sent to all DNS servers that are configured on links with the "DNS default route" option set, as well as
+ the globally configured DNS server.
+
+ If there is no link configured as "DNS default route" and no global DNS server configured, the
+ compiled-in fallback DNS server is used.
+
+ Otherwise the query is failed as no suitable DNS servers could be determined.
+
+
+ The "DNS default route" option is a boolean setting configureable with resolvectl or in
+ .network files. If not set, it is implicitly determined based on the configured DNS domains
+ for a link: if there's any route-only domain (not matching ~.) it defaults to false, otherwise
+ to true.
+
+ Effectively this means: in order to preferably route all DNS queries not explicitly matched by
+ search/route-only domain configuration to a specific link, configure a ~. route-only domain on
+ it. This will ensure that other links will not be considered for the queries (unless they too carry such a
+ route-only domain). In order to route all such DNS queries to a specific link only in case no other link is
+ preferable, then set the "DNS default route" option for the link to true, and do not configure a
+ ~. route-only domain on it. Finally, in order to ensure that a specific link never receives any
+ DNS traffic not matching any of its configured search/route-only domains, set the "DNS default route" option for it
+ to false.
See the resolved D-Bus API
Documentation for information about the APIs systemd-resolved provides.
-