Actual windows11 version seems to have a bug IPV6 DHCPV6 / RA failing

Question

My network has a router connected to the internet. Starting at the router there are multiple VLAN's for different purposes. My PC is connected to two of those vlans's (one at a time). The PC has multiple network interfaces, which I can enable/disable. Each of those interfaces is connected to another VLAN. Only one of those interfaces is active at a certain moment in time. The interfaces obtain there IPV4 & IPV6 addresses form the DHCP-IPV4-server / DHCP-IPV6 - RA server in the router. At least that should happen ... And that did work ..... up to the moment I migrated to Windows11 (64 bit PRO). But ... there is a problem now ....

• IPV4 => No Issue
• IPV6 => One if the interfaces gets IPV6-addresses => OK
• The other interfaces do not get an IPV6-address, or more correct do not even ask the router for an address
  (I checked with wireshark) I spent a lot of time searching the internet for clues and testing. However ... it just does not work :( :( I did connect a windows10 system (also having multiple nic's) to the same vlan's, no problem at all !! So I really have the verdict that there is a bug in the actual windows11 version (win11 pro 64 bit latest patches). Unless my configuration is damaged some where deep in the registry So,
• I hope I am wrong and some one knows how to fix this problem
• I would also appreciate if someone could setup the same kind of config and could confirm my findings Below some extra info

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The PC has in fact 4 interfaces:

• a dual port mellanox 10G card
• a 2.5 G motherboard NIC
• and wifi All are IPV6 enabled One of the mellanox interfaces gets IPV6-addresses. The other mellanox interface and the 2.5G Nic not All VLAN's have (of course) there own subnet-addresses. Windows is not aware of the VLAN's. The VLAN's are terminated on the IP-switch. (The NIC sees an ordinary LAN) The router is pfSense I have on the windows11 system a virtual linux machine, which explains the last part of the ip config example below Below the result of ip config as it should be !! However the bold lines are missing when I switch towards / activate another interface Ethernet adapter 10G-LAN:

Connection-specific DNS Suffix . : priv.lan
IPv6 Address. . . . . . . . . . . : xxxx:yyyy:zzzz:17:d2b3:fc27:f994:ee5a
Temporary IPv6 Address. . . . . . : xxxx:yyyy:zzzz:17:b400:e3d6:ef40:bf61
Temporary IPv6 Address. . . . . . : xxxx:yyyy:zzzz:17:c046:a5b8:8031:62a1
Link-local IPv6 Address . . . . . : fe80::96bd:48d4:eb6f:51fd%18
IPv4 Address. . . . . . . . . . . : 192.168.17.34
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : fe80::6eb3:11ff:fe09:74a%18
192.168.17.1

Ethernet adapter vEthernet (Default Switch):

Connection-specific DNS Suffix . :
Link-local IPv6 Address . . . . . : fe80::5c14:d7d6:6d4f:fce2%50
IPv4 Address. . . . . . . . . . . : 172.22.32.1
Subnet Mask . . . . . . . . . . . : 255.255.240.0
Default Gateway . . . . . . . . . :

Answer 1

I have the same problem with Windows 11 24H2. Is there a fix?