My old laptop has only one wired NIC,it runs Windows Server 2022,i install Mikrotik CHR on Hyper-V .I created a external virtual switch that binds the physical NIC and a virtual machine network adapter that connect to the virtual switch.On CHR,i create a Ethernet interface and a PPPoE interface .In the last few months,devices can‘t open IPv6 websites via wireless router that in bridge mode,because TCP ACK has not arrived at the server,pktmon.exe (Windows network capture packet tool)shows that ACK packets has been sented out from the physical NIC after passing through some network stacks,but the server did‘t respond。
I've disabled all ipv6 firewall filter rules and changed MSS to 1220.
Today,when i turn stateless to stateful and NAT6,it is work good,why is that?

Did you identify the exact link where IPv6 routing breaks?

Did you identify the exact link where IPv6 routing breaks?

In order to securely connect to my home computer at any time from the outdoors like the hacker in the movie, I need IPv6 and a firewall support, but because the IPv6 firewall of the Wireless Modem provided by the ISP is not configurable, I used my old laptop to install mikrotik CHR as a router. And ISP Wireless Modem intercepts DHCP, so i connected another wireless router that works in bridge mode in the middle.Afeter it built, the Hyper-V host, which is my old laptop, works fine with IPv6, so I'm assuming that the wireless modem and wireless router work fine, and besides, they're hard to hack and debug.However, the devices connected through the wireless router do not work properly with IPv6, including wired connections. I compared the packets captured on the device and CHR, but found no difference, except for the hop limit, checksum, and MAC. A few days ago, the device was working fine with stateful and NAT66, so I really can't figure out what went wrong.