Disabling IPv6 In Ubuntu Server 10.04 LTS

Step 1 Run the following command to verify if it is enabled or disabled. 0=enabled & 1=disabled cat /proc/sys/net/ipv6/conf/all/disable_ipv6 Step 2 Using vi add the following lines to /etc/sysctl.conf the # comment is optional but considered a best practice #disable ipv6 net.ipv6.conf.all.disable_ipv6 = 1 net.ipv6.conf.default.disable_ipv6 = 1 net.ipv6.conf.lo.disable_ipv6 = 1 vi Notes Command Function i Enters insert mode (editing) esc exits insert mode :  followed by x saves your work and exits Reboot and run the first command to verify that is has been disabled.
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