Ubuntu networking

Disable IPv6

Create /etc/sysctl.d/60-disable-ipv6.conf

Create a file named /etc/sysctl.d/60-disable-ipv6.conf with this content:

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1

Activate /etc/sysctl.d/60-disable-ipv6.conf

# sysctl -p /etc/sysctl.d/10-disable-ipv6.conf
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1

Check settings

# cat /proc/sys/net/ipv6/conf/all/disable_ipv6
1