From: Bob Sinclair (bob@bobsinclair.net)
Date: Fri Mar 13 2009 - 13:37:23 ARST
Hi All,
It seems that the addresses in the 224.0.0.0/24 range are kept from leaking
to other links by the address range itself, not by the TTL. Cisco implements
both RIP and EIGRP with starting TTL of 2, yet these packets will not be
forwarded off the link if the they are destined to 224.0.0.9, or 224.0.0.10.
To get this protocol traffic to cross to another link (or PVC) we need to
change the destination to unicast, using neighbor statements.
HTH,
Bob Sinclair CCIE 10427 CCSI 30427
www.netmasterclass.net
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
> Dale Shaw
> Sent: Thursday, March 12, 2009 11:58 PM
> To: Nick
> Cc: Cisco certification
> Subject: Re: Well Known Multicast Addresses
>
> Hi Nick,
>
> As Daniel has already pointed out, the third octet for those groups is
> 1, not 0.
>
> 224.0.0.0/24 is reserved for local subnetwork control -- things like
> OSPF, EIGRP, RIPv2, and all that.
>
> I'm not sure how it's enforced, but theoretically everything using
> 224.0.0.0/24 should use a TTL of 1 -- you should never seen
> 224.0.0.0/24 groups leaking beyond the local link.
>
> cheers,
> Dale
>
> On Fri, Mar 13, 2009 at 12:32 PM, Nick <ccieaz@googlemail.com> wrote:
> > Hi All,
> >
> > I was making a quick list of well known multicast addresses and was
> confused
> > about these two, are 224.0.0.39 and 224.0.0.40 used for anything
> major ?
> >
> > Thanks
> > Nick
>
>
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