Howabout:
So they want it messy 
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If you have IP forwarding enabled (using your server as a VPN or similar), you will also need to add the following lines to the /etc/sysctl.conf file. The default settings for these variables (which is 1), prevents IPv6 from working properly when IP forwarding is enabled. You can check if IP forwarding is enabled by running “sysctl net.ipv4.ip_forward”.
net.ipv6.conf.all.accept_ra=2
net.ipv6.conf.eth0.accept_ra=2
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