Hi,
I have a RouterBoard with all 5 ports configured on bridge1 (no routing at all) and I want to use IPv6 SLAAC (StateLess Address AutoConfiguration) to get a dynamic global address.
According to the Wiki [1], “Due to restrictions of IPv6, address auto-configuration can not be performed on routers. Routers require manual address configuration.”
I quite agree with this statement, however my RouterBoard is NOT acting as an IPv6 router, but I still cannot see any way to enable SLAAC on the bridge interface from within WinBox. Am I missing some magic configuration option here?
You’re not missing anything, it’s just not there. RouterOS can only get dynamic IPv6 address from DHCPv6. Which does not help you, if you don’t have DHCPv6 server.
Correction, it does work, but not everything is as expected.
First, accept-router-advertisements is supposed to support unconditional yes. That alone does not work, it still requires forward=no. Then it gets the address, but there’s a catch - it does not show anywhere. It’s not visible in WinBox and neither in CLI (/ipv6 address print does not list it). Ping something external (gateway is enough) and if it works, router got the address. The only way to see it seems to be using Tools->Torch.
I tried to ping the IPv6 address behind ipv6.google.com (dig ipv6.google.com AAAA) and it did work after setting forward to no and accept-router-advertisements to yes. So it seems RouterOS does indeed get autoconfigured via SLAAC. Nice!
In my opinion, SLAAC client has some usefulness on routers - yours is such a situation, but suppose you mostly want to use it to obtain a default GW from an ISP? Mikrotik has a workaround where you can use the dhcpv6-pd server’s address as the default GW - but what if the ISP’s network has a different IP for the DHCPv6-PD server than the router? You’d be screwed in that case - and from the few ipv6-related posts I’ve seen here, the market still hasn’t settled down on a “most common case” for IPv6 - I’ve seen lots of strange things, and sometimes a slaac interface could just be helpful - sure you can’t forward any LANs to a slaac client - but it might still be a helpful thing to have in the toolbox…
In my case I just needed a DNS cache (the ISP box can’t query any other servers than the hardcoded resolvers) and traffic shaping, but no routing. So there are definitely some valid use cases.
please study IPv6 and how it works before making wild posts. IPv6 while similar is much better thought over than IPv4 is.
First of, on IPv6 network infrastructure you are not required to have global Ipv6 addresses at all. Only the network with end user hosts and interfaces connected to that network should have an IPv6 address, IPv6 address can be used for management only. All the networking stuff will and can happen using Link-local addresses.
The address you get will be Prefix + MAC address with the “usual” parts added to comply with EUI64.
Yes, there is some technical issues why RouterOS does not show this address in the address list.
Also, IPv6 has redirect message that end user hosts has to obey if received - that is, if network infrastructure knows a better route to the host via another router in the same network, it can send the redirect to the end user host. After that, the end user host has to send all the traffic using gateway as indicated in redirect host.
