[[!comment format=mdwn username="david" avatar="http://cdn.libravatar.org/avatar/22c2d800db6a7699139df604a67cb221" subject="probably low level is needed" date="2019-07-19T12:38:30Z" content=""" A tiny amount of investigation reveals that there are protocols that make sense only for one of ip{6,}tables, e.g. icmpv6. So probably ip6tables needs to be invoked separately. """]]