An Clients habe ich es mit drei Android-Geräten und einem Notebook mit Linux Mint probiert, bei allen dasselbe Verhalten. Deswegen vermute ich das Problem eher nicht bei den Clients.
Beim Linux MINT diesem liefert ohne aktiven VPN "ip addr show":
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host noprefixroute
valid_lft forever preferred_lft forever
2: enp0s31f6: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN group default qlen 1000
link/ether f8:75:a4:6e:51:88 brd ff:ff:ff:ff:ff:ff
4: wlp0s20f3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 4c:1d:96:b4:d3:04 brd ff:ff:ff:ff:ff:ff
inet 192.168.205.49/24 brd 192.168.205.255 scope global dynamic noprefixroute wlp0s20f3
valid_lft 861256sec preferred_lft 861256sec
inet6 2003:e5:971c:9a00:e618:b8cc:6d72:6a75/64 scope global temporary dynamic
valid_lft 7011sec preferred_lft 1610sec
inet6 2003:e5:971c:9a00:1d1b:341f:8460:16c4/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 7011sec preferred_lft 1610sec
inet6 fd4c:689d:bbbb:0:2333:7cb0:a84a:a1b1/64 scope global temporary dynamic
valid_lft 7011sec preferred_lft 3411sec
inet6 fd4c:689d:bbbb:0:2c5d:a2e9:6678:7456/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 7011sec preferred_lft 3411sec
inet6 fe80::1253:8a0f:bb15:ae37/64 scope link noprefixroute
valid_lft forever preferred_lft forever
55: wwan0: <BROADCAST,MULTICAST,NOARP> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether ea:48:08:72:e8:b8 brd ff:ff:ff:ff:ff:ff
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host noprefixroute
valid_lft forever preferred_lft forever
2: enp0s31f6: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN group default qlen 1000
link/ether f8:75:a4:6e:51:88 brd ff:ff:ff:ff:ff:ff
4: wlp0s20f3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 4c:1d:96:b4:d3:04 brd ff:ff:ff:ff:ff:ff
inet 192.168.205.49/24 brd 192.168.205.255 scope global dynamic noprefixroute wlp0s20f3
valid_lft 861256sec preferred_lft 861256sec
inet6 2003:e5:971c:9a00:e618:b8cc:6d72:6a75/64 scope global temporary dynamic
valid_lft 7011sec preferred_lft 1610sec
inet6 2003:e5:971c:9a00:1d1b:341f:8460:16c4/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 7011sec preferred_lft 1610sec
inet6 fd4c:689d:bbbb:0:2333:7cb0:a84a:a1b1/64 scope global temporary dynamic
valid_lft 7011sec preferred_lft 3411sec
inet6 fd4c:689d:bbbb:0:2c5d:a2e9:6678:7456/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 7011sec preferred_lft 3411sec
inet6 fe80::1253:8a0f:bb15:ae37/64 scope link noprefixroute
valid_lft forever preferred_lft forever
55: wwan0: <BROADCAST,MULTICAST,NOARP> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether ea:48:08:72:e8:b8 brd ff:ff:ff:ff:ff:ff
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host noprefixroute
valid_lft forever preferred_lft forever
2: enp0s31f6: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN group default qlen 1000
link/ether f8:75:a4:6e:51:88 brd ff:ff:ff:ff:ff:ff
4: wlp0s20f3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 4c:1d:96:b4:d3:04 brd ff:ff:ff:ff:ff:ff
inet 192.168.205.49/24 brd 192.168.205.255 scope global dynamic noprefixroute wlp0s20f3
valid_lft 861256sec preferred_lft 861256sec
inet6 2003:e5:971c:9a00:e618:b8cc:6d72:6a75/64 scope global temporary dynamic
valid_lft 7011sec preferred_lft 1610sec
inet6 2003:e5:971c:9a00:1d1b:341f:8460:16c4/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 7011sec preferred_lft 1610sec
inet6 fd4c:689d:bbbb:0:2333:7cb0:a84a:a1b1/64 scope global temporary dynamic
valid_lft 7011sec preferred_lft 3411sec
inet6 fd4c:689d:bbbb:0:2c5d:a2e9:6678:7456/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 7011sec preferred_lft 3411sec
inet6 fe80::1253:8a0f:bb15:ae37/64 scope link noprefixroute
valid_lft forever preferred_lft forever
55: wwan0: <BROADCAST,MULTICAST,NOARP> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether ea:48:08:72:e8:b8 brd ff:ff:ff:ff:ff:ff
Die Datei /etc/resolv.conf enthält:
nameserver 127.0.0.53
options edns0 trust-ad
search fritz.box
"ip route show" liefert
default via 192.168.205.1 dev wlp0s20f3 proto dhcp src 192.168.205.49 metric 600
192.168.205.0/24 dev wlp0s20f3 proto kernel scope link src 192.168.205.49 metric 600