[Xorp-users] R: Re: R: RE: ospfv3 interfaces on the same link with different network prefixes

[maxd at inwind.it]

That would be useful. Can you also send me your network interface configuration 
(ifconfig or ip addr)?
To understand why it does not work, consider a simple scenario with three 
nodes: A ---- B ---- C. B has clearly two network interfaces.
Now, suppose that each interface has  a link local address + a site local 
address. If I want to ping C from A, I need to use C site local address. 
According to the behaviour of XORP I am experiencing, the site local address of 
C will show up in the routing table of node A, but not in the one of node B. 
So, A knows that the message for C must be forwarded to B. B does not know a 
route for the site-local address of C, and it does not matter that he knows the 
link-local address of C. I mean, B does not know that the node attached on the 
other side of the link, for which he has a link-local entry in the routing 
table, is the intended recipient of the message. I hope that I have clarified 
the issue...

Thanks for your help,
Massimiliano


>----Messaggio originale----
>Da: p_latini at hotmail.com
>Data: 29/06/2011 21.17
>A: "maxd at inwind.it"<maxd at inwind.it>
>Ogg: Re: R: RE: [Xorp-users] ospfv3 interfaces on the same link with 
different	network prefixes
>
>I do not have that configuration with different site local prefixes. But in 
any case xorp uses and sets the link local addresses for the next hop in the 
router table. So even if you dont have any site local address inthe link 
between the xorp and router it sould work anyways.
>
>If you want i can send you an output of my xorp router table where shows that 
it uses LL addreses.
>
>Patricio
>
>Sent from my iPad
>
>On Jun 29, 2011, at 4:14 AM, "maxd at inwind.it" <maxd at inwind.it> wrote:
>
>> Hi Patricio,
>> thanks for your answer. I want to be sure that I was clear enough about 
the 
>> issue I have.
>> In a scenario like yours, I see that you have three network segments:
>> -Internet---Xorp
>> -Xorp---Router
>> -Router-host
>> Let's consider the Xorp---Router segment. I understand that you have more 
than 
>> one address on each interface. Let's consider the site local addresses on 
this 
>> segment. The Xorp node will have a site local address, say it SL_ADDR_XORP, 
and 
>> the same will be for the router, say it SL_ADDR_ROUTER. In your network 
>> scenario, SL_ADDR_XORP and SL_ADDR_ROUTER, do they share the same network 
>> prefix? By network prefix I mean the network part of the address (e.g., 
the 
>> first 64 bit of the address if you have a /64 mask). In my configuration, 
they 
>> do not share the same network prefix (I need to have this configuration), 
and 
>> what I get is that, projecting the behaviour I am experiencing on your 
network 
>> topology, the Xorp node will not have an entry in the routing table for 
>> SL_ADDR_ROUTE, and the same will be for the router. 
>> Do you experience a different behaviour?
>> 
>> Thanks again,
>> Massimiliano
>> 
>> 
>>> ----Messaggio originale----
>>> Da: p_latini at hotmail.com
>>> Data: 28/06/2011 19.49
>>> A: <maxd at inwind.it>, <xorp-users at xorp.org>
>>> Ogg: RE: [Xorp-users] ospfv3 interfaces on the same link with 
different    
>> network prefixes
>>> 
>>> Massimiliano:
>>> 
>>> Yes, I have a Internet---Xorp---Router---host configuration with three
>>> addresses between xorp box and the router (Link Local, site local and
>>> global). Xorp is generating the default route and propagating it to the
>>> router, also it is learning the site local and global networks configured 
on
>>> the hosts side of the router.
>>> 
>>> So far, no problem.
>>> 
>>> Patricio
>>> 
>>> -----Original Message-----
>>> From: xorp-users-bounces at xorp.org [mailto:xorp-users-bounces at xorp.org] On
>>> Behalf Of maxd at inwind.it
>>> Sent: Tuesday, June 28, 2011 2:18 PM
>>> To: xorp-users at xorp.org
>>> Subject: [Xorp-users] ospfv3 interfaces on the same link with different
>>> network prefixes
>>> 
>>> Hi,
>>> I have a network in which each network interface has two addresses: a 
link-
>>> local one (assigned by the IP Stateless ZeroConf mechanism) and a site-
local
>>> one. The site-local address has a different network prefix for each 
network
>>> interface, i.e., network interfaces attached on the same link do not share
>>> the same network prefix. Has anyone tried this configuration? I cannot get
>>> it to work with XORP: each node is missing the route entries towards the
>>> nodes attached on the same network segment. Notice that the same network
>>> scenario is managed  fine by QUAGGA. 
>>> 
>>> Thanks for your help!
>>> Massimiliano
>>> 
>>> _______________________________________________
>>> Xorp-users mailing list
>>> Xorp-users at xorp.org
>>> http://mailman.ICSI.Berkeley.EDU/mailman/listinfo/xorp-users
>>> 
>>> 
>> 
>> 
>