Post #224302

Been troubleshooting the weirdest connectivity issue at home. My current setup is a GPON router provided by my ISP with PPPoE Passthrough enabled. Then I have a Mikrotik router plugged into that which connects to PPPoE and receives an IPv6 prefix to spread via SLAAC. It all works perfectly fine... Except when I try to connect to a specific Microsoft-controlled subnet (2620:1ec::/36) via HTTPS a few packets go missing on the way to me that causes the connection to hang and eventually time out. I've sniffed the connection at every part of the chain I could. On the router itself, by inserting a switch with traffic mirroring enabled between the Mikrotik and ISP router, and it seems that some packets just don't arrive. It seems to specifically be https that is affected, and only when connecting to that specific subnet. And for extra fun, if I just plug into the ISP router (which has a separate prefix delegated because I can't switch it to plain bridge mode) everything works fine.