sudo nmcli connection modify "Verbindung per Kabel 1" \
  ipv6.addresses "2a01:04f8:0262:4cc4:0000:0000:0000:0001/64" \
  ipv6.gateway "fe80::1" \
  ipv6.method manual

sudo nmcli connection up "Verbindung per Kabel 1"

ip -6 addr show ens19
ip -6 route show
ping6 google.com

nameserver 2001:4860:4860::8888
nameserver 2001:4860:4860::8844

ping connectivity-check.ubuntu.com

sudo nano /etc/default/grub
GRUB_CMDLINE_LINUX="ip=2a01:4f8:262:4cc4::1::64:fe80::1:ens18"
sudo update-grub