SLAAC for IPv6 address assignment

RouterOS General
1

I am using RB750GL with RouterOS 6.37.1 and WinBox

I can’t get SLAAC working on my RouterBoard’s WAN interface (ether1-gateway).
Using Tools > Packet Sniffer, I can see that the RA messages from my upstream router DO have a Prefix Information Option with a valid prefix.
But the RouterBoard doesn’t autoconfigure an address.
When I add a DHCPv6 client, I can Request address (IA-NA) and/or Request prefix (IA-PD). But there doesn’t seem to be any SLAAC-only option.

I subsequently found that the manual page on IPv6/ND states:

Due to restrictions of IPv6, address auto-configuration can not be performed on routers. Routers require manual address configuration.

But I thought it was a requirement in RFC 7084?

WAA-1: The IPv6 CE router MUST support Stateless Address Autoconfiguration (SLAAC) [RFC4862]

I have posted a related question on the Network Engineering StackExchange site:
https://networkengineering.stackexchange.com/questions/35908/should-a-router-use-slaac-for-ipv6-address-assignment

2

first, lets quote the RFC you pointed to:

This document is not an Internet Standards Track specification;

Now when this is sorted head over to ‘/ipv6 settings’ menu (in CLI) and set

accept-router-advertisements=yes

forgot the caveat - assigned address will not be displayed anywhere in GUI/CLI. But it will be standard EU64 conversion of the prefix and the MAC address of the interface. You can ping it, connect to it etc.

3

Well, but.. why is it not mentioned anywhere? Could it be displayed in IPv6 Addresses, with some flag?

4

Why? Are you just wanting another way to get to the router if IPv4 doesn’t work by chance? Just interested in knowing is all.

Seems like SLAAC and DHCPv6-client should be able to both work at the same time… Do you plan on using both?

5

I do think this is something the communities and your team really need to iron out. With MikroTik lacking address assignment for IPv6 via DHCP (DHCPv6) and the RFC indicating RA’s should be heard (because by default DHCPv6 really isn’t supposed to have an add-default-route option). We may need to look at the Linux kernel’s carte-blance approach of accepting RAs or not and seek out a per-interface type of setting. That said, it’s fairly trivial to filter out RAs on “internal” interfaces where you’d typically want them ignored. This also would aid in protecting against MITM attacks by malicious RAs but would require the IPv6 filter (bridge filter) in place and the necessary processing power.

Personally, I like IPv6 DHCP client for address and prefix assignment with the default route work-around. It just works.

I’m doing some off-the-shelf device testing of consumer routers in regards to NAT64 / DNS64 on IPv6 only ISP connections. I intend to clarify each units functionality when it comes to how it assigns its WAN IP and obtains it’s default route in hopes of clarifying how they are setup to get on the IPv6 only net. Hopefully this research will also clarify whether or not the Linux community needs to look at narrowing the scope of RA from system-wide to per-interface in order to comply with how connections will be handed off in the future.