Until recently, IPv6 was perpetually on my “deal with it later” list. I’m sure it’s the same story for many home lab enthusiasts. We all know IPv6 exists, and that IPv4 is living on borrowed time, which has been continually extended by various NAT workarounds that were never meant to be permanent fixes. As long as everything on my network kept working, IPv6 felt easy to ignore. Then, my ISP quietly transitioned to IPv6, and I realized it left a security hole in my firewall rules that I hadn’t anticipated.