Useless Linux Kernel Error Messages

I run lots of Linux-based software routers on my home network to route IPv4 and IPv6. Periodically, they freak out with some IPv6-related errors that seem to indicate a problem but there is no corresponding forwarding impact. Here are two of them: (trill:18:56:EDT)% dmesg tail[40878917.324479] ICMPv6: Received fragmented ndisc packet. Carefully consider disabling…