Disabling the IPv6 in Ubuntu systems

May be some of you have a issue with the slow internet connection in your Ubuntu installations. This could be happend due the ipv6 support. I don't exactly know why of this behavior, but after disable it, my internet connection goes more faster. Let's see how to fix that:

1.- First, make sure that the ipv6 support it's enabled on your machine. To do so, enter the following in the command line:

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

That command will echoed a number, if the resulting number it's "0" means that the ipv6 support it's enabled, if the resulting number it's "1" means that the ipv6 it's disabled.

2.- Now we need to add some lines to the /etc/sysctl.conf configuration file. To do so in the command line, we need to enter the following:

echo "#disable ipv6" | sudo tee -a /etc/sysctl.conf

echo "net.ipv6.conf.all.disable_ipv6 = 1" | sudo tee -a /etc/sysctl.conf

echo "net.ipv6.conf.default.disable_ipv6 = 1" | sudo tee -a /etc/sysctl.conf

echo "net.ipv6.conf.lo.disable_ipv6 = 1" | sudo tee -a /etc/sysctl.conf

3.- In the end, we need to restart the machine and the ipv6 support will be disabled.