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I've added blacklist ipv6 to my blacklist.conf file to keep the ipv6 module from loading, but there's a lot of other modules related to ipv6 as well that I'd like to know if I can add to the list as well. For example: ip6t_LOG ip6t_rt ip6table_filter ip6_tables Is it safe to unload these modules as well or are they needed for proper and safe functionality of iptables and ipv4?

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(One wonders why you want to blacklist IPv6. Isn't IPv6 what we're all supposed to be migrating to?)

Those other modules aren't necessary for IPv4 functionality, so you can safely blacklist them. On the other hand, you shouldn't need to bother blacklist them because nothing should be causing them to load anyway unless you're trying to configure some ip6tables rules... and even if they load, they won't have any effect anyway if there is no IPv6 packet processing going on.

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Maybe I need to do more research, my understanding is if your local network isn't using ipv6 there's no need to having it configured on your machines, that being the case the more unneeded kernel modules loaded the more memory is used. The output of lsmod showed all these modules loaded. I'm certainly no expert on this though, thus the question. – dginsd Jul 13 '12 at 1:17
What you really should do is set up a tunnel and start using IPv6. But as written, if you don't have a tunnel, you will not use them. So no need to blacklist them. – Anders Jul 15 '12 at 4:45

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