The use of .0/.255 addresses.

Paul Jakma paul at clubi.ie
Sun Jun 27 22:47:08 UTC 2004


On Sun, 27 Jun 2004, Iljitsch van Beijnum wrote:

> If you want to have some real fun, try configuring some class E 
> addresses. Windows of course won't have it, and Cisco also doesn't 
> want anything to do with it, even to the point of rejecting routes 
> within 240.0.0.0/4 when they come in over BGP. (Which an MacOSX box 
> running Zebra will happily provide.)

Class D you mean surely?

Note that while GNU Zebra might be configurable to provide such 
updates, it too rejects such updates if received on unicast IPv4 
address family sessions bgp_route.c::bgp_nlri_parse():

       /* Check address. */
       if (packet->afi == AFI_IP && packet->safi == SAFI_UNICAST)
         {
           if (IN_CLASSD (ntohl (p.u.prefix4.s_addr)))
             {
               zlog (peer->log, LOG_ERR,
                     "IPv4 unicast NLRI is multicast address %s",
                     inet_ntoa (p.u.prefix4));
               bgp_notify_send (peer,
                                BGP_NOTIFY_UPDATE_ERR,
                                BGP_NOTIFY_UPDATE_INVAL_NETWORK);
               return -1;
             }
         }

and has done since GNU Zebra 0.91.

regards,
-- 
Paul Jakma	paul at clubi.ie	paul at jakma.org	Key ID: 64A2FF6A
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Fortune:
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 		-- Publilius Syrus



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