Wyłączenie IPv6

echo "net.ipv6.conf.all.disable_ipv6 = 1" >>/etc/sysctl.conf

echo "net.ipv6.conf.default.disable_ipv6 = 1" >>/etc/sysctl.conf

sysctl -p

sysctl -w net.ipv6.conf.all.disable_ipv6=1
sysctl -w net.ipv6.conf.default.disable_ipv6=1

ifconfig | grep inet6