How do I disable IPv6 on Debian/Ubuntu?
Disable IPv6 on all interfaces in the kernel with: # sysctl net.ipv6.conf.all.disable_ipv6=1 Save the setting so that it stays disabled at the next boot: # echo net.ipv6.conf.all.disable_ipv6=1 > /etc/sysctl.d/60-no_ipv6.conf