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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