I did some more tests. Using "dns-search=my.domain" and "ignore-auto-dns=true" actually works for wifi connections. For VPN (vpnc) is does not work.
The tool "systemd-resolve --status" still shows a tilda before the domain name ("DNS Domain: ~my.domain" instead of "DNS Domain: my.domain") and the name lookup for computers in my.domain does not work without giving the FQDN.
I did some more tests. Using "dns-search= my.domain" and "ignore- auto-dns= true" actually works for wifi connections. For VPN (vpnc) is does not work.
The tool "systemd-resolve --status" still shows a tilda before the domain name ("DNS Domain: ~my.domain" instead of "DNS Domain: my.domain") and the name lookup for computers in my.domain does not work without giving the FQDN.