tpe

Hi @ret, The only thing I changed was the IPv6 address assignment of the internal downlink interface "vlan2" where the windows computers are connected. Here is a picture of the modified settings: SLAAC needs to be disabled, and I also assigned a global address to the interface using DHCPv6 prefix delegation and a static…

Thanks @Ian31, that seems to have solved my problem! I disabled SLAAC on vlan2 interface and configured it to use DHCPv6 prefix delegation instead, and now the Router bit is set in ICMPv6 NA packets. After one hour of testing I haven't observed anything weird with the gateway configuration anymore.