Man pages matching name dnsdomainname in section 1:

dnsdomainname.1.en	debian 10 / hostname
dnsdomainname.1.de	debian 10 / manpages-de
dnsdomainname.1.es	debian 10 / manpages-es-extra
dnsdomainname.1.ja	debian 10 / manpages-ja
dnsdomainname.1.pl	debian 10 / manpages-pl
dnsdomainname.1.tr	debian 10 / manpages-tr
dnsdomainname.1.en	debian 11 / hostname
dnsdomainname.1.de	debian 11 / manpages-de
dnsdomainname.1.es	debian 11 / manpages-es
dnsdomainname.1.ja	debian 11 / manpages-ja
dnsdomainname.1.pl	debian 11 / manpages-pl
dnsdomainname.1.tr	debian 11 / manpages-tr
dnsdomainname.1.en	debian 12 / hostname
dnsdomainname.1.de	debian 12 / manpages-de
dnsdomainname.1.es	debian 12 / manpages-es
dnsdomainname.1.ja	debian 12 / manpages-ja
dnsdomainname.1.pl	debian 12 / manpages-pl
dnsdomainname.1.tr	debian 12 / manpages-tr