Hi, is there a way to permanently disable the IPv6 DHCP server and only use SLAAC to assign IPv6 addresses in the LAN? Thanks.
To answer this question by my self after extensive searches...
Interfaces -> LAN:
IPv6 Configuration Type = Track Interface
Manual configuration = Allow manual adjustment of DHCPv6 and Router Advertisements
Then there is a sub menu [LAN] under Services -> DHCPv6. In there I can turn off DHCPv6 server for the LAN interface.
There is also a sub menu [LAN] under Services -> Router Advertisements. I changed it to Unmanaged.
In addition, the interface -> wan -> DHCPv6 client configuration -> Prefix delegation size must be accurate, such as 60 instead of 64, otherwise the prefix in the RA received by the client is 60 bits instead of 64 bits, so the client cannot use slaac mode to generate ipv6