How can i request a ipv6 prefix from the Router to delegate for the internal Lan?
The PC is assigned an IPv6 on the external interface, but how do I get an IPv6 prefix for the internal interface?
According to my ISP, the router should be able to prefix delegation.
When you connect to a network, a number of automatic network configurations are performed, and a few relate to IPv6 configuration (and auto configuration).
One is Steless Address Autoconfguration (SLAAC).
This means that every device automatically generates an IPv6 address based on the network prefix obtained from the router or other devices in the network.
If your ISP wishes to do so when you were on the outside of your network, DHCP may be used to assign another address which can be used.
In fact, the last time I looked at my machine, it had approximately 4 different IPv6 addresses for different reasons.
Any of the addresses can be used.
You can read up more on SLAAC for yourself,
And perform the following to display all your network interfaces and addresses assigned to each of them
Probably easiest way to identify your network prefix is to compare your IPvv6 addresses to addresses of other devices on your network.
You should first determine if your Gateway router can be configured to forward IPv6.
If not and you <really> want an IPv6 address that works from behind your Gateway router, then you’ll need a tunnel broker.
AFAIK they’re all free.
Or, go back to your previous configuration which is to place your machine in front of your Router and if you want this machine to communicate with other machines in your network, will have to architect how that works (many possible solutions depending on actual situation and need).
The first step is to find out whether your Router can delegate prefix in the first place.
IPv6 prefix delegation is designed to be used by your ISP router. I.e. your router (requesting router per standard) requests prefixes from your ISP, and then distributes them downstream (i.e. to your PC on your diagram) using normal RA mechanism. That is likely what your ISP means. Are you sure your Router is capable to function as prefix delegating router (quoting standard again) subdividing further prefix it gets?
Assuming it is, the simplest way would be to use NetworkManager on PC; it supports prefix delegation via “ipv6.method=shared” address configuration on downstream interface.
Yes, according to the provider of which the router is, it should work.
I’m supposed to get a / 56 prefix. End devices on the router get a / 64 prefix. Routers behind the ISP router should be able to receive prefixes e.g. /62 or /60.
Work NetworkManager headless too? Thought NetworkManager only works in the desktop, that’s why I used Wicked.
Thought NetworkManager only works in the desktop, that’s why I used Wicked.
NetworkManger is server that manages interfaces according to defined connection profiles. Desktop component allows you to edit connections and request activation of specific connection profile on specific interface, but actual job is done by server. To manage connections (and NetworkManager in general) without GUI you can use nmcli or nmtui.
I have only one statement from the ISP after a request for prefix delegation
Theoretisch bekommt die Connect Box von WAN Seite eine IP-Adresse für sich selbst. Dann fordert sie ein Präfix an, welches auf diese Adresse geroutet wird. Beispielsweise würde auf die Adresse ::1300:0:0:0:1 das Präfix ::4200:0:0:0:0/56 geroutet – man sieht, dass zwischen den beiden kein Zusammenhang besteht. Die Connect Box nimmt jetzt das zugeteilte Präfix und teilt es auf – sie benötigt ein /64 für ihre LAN-Seite, z.B. ::4200:0:0:0:0/64 – das heißt, alle Clients direkt an der Connect Box können eine Adresse in diesem Bereich bekommen. Man kann aber aus diesem LAN-Bereich keine weitere Präfixe verteilen, weil das Netz bereits die minimale Größe für ein Ethernet Interface erreicht hat. Daher stellt die Connectbox aus dem übrigen Bereich Ihres eigenen Präfixes Subnetze bereit, welche für Prefix-Delegation verwendet werden können. Beispielsweise könnte ein Router im LAN der Connectbox die Adresse ::4200:0:0:0:1 bekommen und das Präfix ::4280:0:0:0:0/62. Der nächste Router mit der Adresse ::4200:0:0:0:2 bekommt möglicherweise das Präfix ::42A0:0:0:0:0/60. In jedem Fall sind die Präfixe unterschiedlich voneinander und unterschiedlich vom LAN-Präfix der Connectbox. Falls Du weitere Fragen hast, melde Dich gern jederzeit wieder bei uns. Ich wünsche Dir einen angenehmen Tag.
I didn’t get any further with the NetworkManger and found that some things didn’t work properly in this constellation. (DNS, Firewalld, …)
Will ask my provider again if this router really supports prefix delegation.
Maybe someone has an idea how I could check if the router distributes prefixes?
Oh yes, there is – Page 24 – DHCPv6 Server – Stateful or Stateless – default: Stateless – start address: 2a02:908:f519:d180::/64 …
Did you, by chance, choose “Stateful”?
Possibly not a good idea – the resulting load on your Router will be rather more than that, which will be the case with the choice of “Stateless” …
By the way, simply let your Router be the DHCP server for your LAN – household routers supplied by (German) ISPs only generate private IP addresses for your household LAN/WLAN – die Bundesnetzagentur will es nicht anders haben …
And, AFAIK, the DSL link from from your residence to Vodafone is also private – to Vodafone – because it also carries your VoIP telephony – once again the Bundesnetzagentur …
If you wish to inspect what’s going on, use <https://www.iplocation.net> – it will first indicate your Router’s IPv4 address as seen by the world, probably at a location you didn’t expect at all «the physical location of Vodafone’s Internet Gateway» – take a look into your Router – you’ll find the IPv6 address Vodafone assigned to your Router – then drop that IPv6 address into iplocation.net – probably yet another unexpected location …
Well, it looks better than in my case - at least your DHCPv6 server actually understands and responds to PD request. There are quite a lot of discussions in Internet about PD with your router (both Vodafone and other providers). It looks like your router has severe limitations - several threads suggest that it is capable of delegating exactly one /60 prefix and fails if anything else is requested.
Unfortunately dhclient is pretty limited in this regard. You may try to manually run dhcpcd which has much better support and allows requesting specific prefix length.
Another threads say that PD stopped working since beginning of this year unless you have extra agreement (and pay extra money).
I would suggest asking on your ISP forums as well.
Taking the information from my Laptop and my (German) ISP – another one – the “blue” one – the DSL Router is an AVM FRITZ!Box 7490 – my Desktop uses wicked and therefore, dhclient is blocked …
I do not have a fixed public IP address, my contract does not include a dual stack clause and, the DSL also carries my VoIP telephone traffic …
You aren’t a major ISP, so you don’t need a registered block of addresses from APNIC.
The way IPv6 works, as long as you use an address that uses the same prefix as your gateway router, you are routable to the Internet (and vice versa).
There is no such thing as IPv6 NAT (or at least, it’s highly discouraged because there are many reason not to configure and hardly any good reason to deploy).
If you want a larger bit prefix, why not just grab some unused part? It’s easy to test whether those addresses are already used and as vast as the address space is, it’s unlikely that anyone would notice what you’ve done. Unless you were actually stepping on someone else, I can’t imagine an ISP would care whether you do this.
IPv6 DHCP might be implemented only for management purposes so that new hosts might be grouped into contiguous addresses. But, it’s not required to acquire a working IP address like in IPv4. The self-generated IPv6 address is considered to be perfectly usable unlike IPv4. And IPv6 DHCP ordinarily grants you a very large block of usable addresses, ie 64 bits. An ISP would have to be incredibly miserly to do otherwise.
As an ISP, you might have an interest in this topic.
As a customer/User, I’m having a bit harder time seeing a use case.
This is more or less consistent with discussions and presentations I’ve seen, but maybe I just haven’t spoken to the right people…