By default all major distributions of Linux nowadays are IPv6 enabled.
That is true also for Ubuntu server v6.06.1 aka Dapper Drake.
Sometimes leaving IPv6 enabled can cause little annoyances.
Fire up your favourite text editor and sudo edit this file
/etc/modprobe.d/aliases
Replace the line alias net-pf-10 ipv6 with alias net-pf-10 off.
Restart the computer and check the result with this line
ip a | grep inet6
If nothing appears IPv6 has gone :-)
Read here the original article
