Hi! I have this - can anyone help explain how NDP Proxy hybrid mode differs? ( Whoever said this is well documented is hallucinating )
Once that's done, I can add this as help fields to LuCI under DHCP-> IPv6 and make a PR.
Router-Advertisement Service: RA is a subset of NDP. NDP is a subset of ICMPv6.
disabled: RA is off
server mode: RA is on; Router advertises itself as the default IPv6 gateway to downstream devices, sends RA messages (ICMPv6 type 134, to ff02::1) to LAN, and provides PD (Prefix Delegation) to downstream devices.
relay mode: Router relays RA from upstream, and extends upstream (WAN) interface config and prefix to downstream (LAN) interfaces.
hybrid mode: Router does both server+relay; extends upstream config and prefix downstream, and uses PD (Prefix Delegation) locally.
DHCPv6 Service:
disabled: No DHCPv6 runs.
server mode: DHCPv6 runs and router assigns addresses to downstream devices and delegates prefixes (PD) to downstream interfaces.
relay mode: Router relays WAN interface config downstream. Helps to support uplinks without Prefix Delegation (PD).
hybrid mode: Router does combination of server+relay.
NDP Proxy: Neighbour Discovery Protocol Proxy - reverts to disabled internally if there are no interfaces with boolean 'ndproxy_slave' set to 1. Think of NDP Proxy as Proxy ARP for IPv6: unify hosts on different physical hardware segments into the same IP subnet. Consists of NS (Solicit) and NA (Advertisement) messages. NDP listens for NS on an interface marked with boolean 'master' as 1 (i.e. upstream), then queries the slave/internal interfaces for that target IP before finally sending an NA message. NDP is effectively ARP for IPv6. NS and NA detect reachability and duplicate addresses on a link, themselves also a prerequisite for SLAAC autoconfig.
disabled: No NDP messages are proxied through to 'ndproxy_slave' true interfaces.
relay mode: Proxies NDP messages from master to 'ndproxy_slave' true interfaces. Helps to support provider links without Prefix Delegation (PD), and to firewall proxied hosts.
hybrid mode: Relay mode is disabled unless the interface is a master interface, i.e. its boolean 'master' is 1.
DHCPv6 Mode:
stateless: Prefix is advertised and host uses SLAAC (a host assigns its own address) - Stateless Address Auto Config. No DHCPv6.
stateless + stateful: SLAAC. In addition, router assigns an IPv6 address to a host via DHCPv6.
stateful-only: No SLAAC. Router assigns an IPv6 address to a host via DHCPv6.