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I labbed it up using my own hub and spokes and different addresses than you so it probably doesn’t make sense for me to show you my configuration.
Steps: On both spokes use “passive tunnel” under the ospf routing processes. I used for tunnel source and destination the serial interfaces like you. A static mroute on R2 back to the source of the ping like the tunnel interface on R4. pim dense-mode on both tunnel interfaces.
Just the multicast packets will take the tunnel route (encapsulation) and not unicast packets.
-Rich

On 4/27/08, Ahsan Mohiuddin wrote: > > Hello Rich, > > thanks for taking an interest in my problem. the ip address i am using for > unnumbered tunnel (loopback) is known via ospf area 0 but its known out the > serial, and not the tunnel. For example, if I use R4’s loopback for the > unnumbered tunnel (150.1.4.4), R2 knows this address not out the tunnel > but out the serial (FR) interface going to hub R5. That defeats the purpose > of the tunnel. it will become clearer when u lab it up. > > thanks once again > > On Sun, Apr 27, 2008 at 7:21 PM, Rich Collins wrote: > > > Hi, > > > > I will try to lab it up tomorrow. I think that the interfaces you are > > using for the unnumbered should already be known in the routing table or > > pick a loopback that is known via a routing protocol. > > > > -Rich > > > > > > On 4/26/08, Ahsan Mohiuddin wrote: > > > > > > Hello, > > > > > > i just came up with one more possibility. We could run eigrp 20 on R2 > > > and R4’s loopback 0 and unnumbered tunnel interfaces. The eigrp routes (to > > > remote router’s loopback) will be preferred over OSPF routes. Thereby, ping > > > to multicast group from R4 will cause the packets to take the tunnel rather > > > than the FR cloud. The question is, is it valid to add a routing domain, > > > which the lab does not ask you to create? > > > > > > I have seen IE’s solution guide for this lab but apparently it > > > suggests nothing to overcome this problem. I would be grateful if Brian D. > > > or Brian M. could shed some light. > > > > > > Thanks > > > > > > On Sat, Apr 26, 2008 at 8:50 PM, Ahsan Mohiuddin > > ahsan.mohiuddin@gmail.com> wrote: > > > > > > > Hello again, > > > > > > > > I formed a tunnel between spokes and it works fine when i put ip > > > > addressing over the tunnel. THat is, I am able to ping mcast addr > > > > 228.22.22.22 from R4. R2 sees this as a source for this group out > > > > the tunnel interface. > > > > > > > > However, once i use unnumbered on the tunnel, R4 cannot send ping > > > > packets out the tunnel interface. So, well we are back to square 1; R4 sends > > > > packets out to to R5 over FR. Since we are running dense mode, ip pim > > > > nbma-mode is useless and R5 will not forward out the same interface on which > > > > it received the packets. > > > > > > > > Any ideas how to make R2 receive ping packets from R4 over the > > > > unnumbered tunnel? > > > > Thanks > > > > > > > > > > > > On Sat, Apr 26, 2008 at 2:08 PM, Ahsan Mohiuddin > > > ahsan.mohiuddin@gmail.com> wrote: > > > > > > > > > much thanks.. i wonder why unnumbered never crossed my mind! > > > > > > > > > > > > > > > On Sat, Apr 26, 2008 at 1:55 AM, Rich Collins > > > > > wrote: > > > > > > > > > > > yes. Probably you are allowed “ip unnumbered addresses for the > > > > > > GRE tunnel”. You have to then be careful about active routing protocols > > > > > > which will broadcast/multicast over this tunnel. You might need to declare > > > > > > the tunnel interface as passive. > > > > > > > > > > > > You also most likely will need a static mroute. > > > > > > Watch for any RFP failures. > > > > > > > > > > > > i.e. > > > > > > *Mar 1 00:31:41.631: IP(0): s=192.168.5.5 (Tunnel1) d= > > > > > > 228.22.22.22 id=30, ttl=253, prot=1, len=100(100), not RPF > > > > > > interface > > > > > > > > > > > > -Rich > > > > > > > > > > > > On 4/25/08, Ahsan Mohiuddin wrote: > > > > > > > > > > > > > > like GRE tunnel? I don’t know bcuz the lab instructions > > > > > > > specifically ask NOT to add any IP Addressing thats not there in the diagram > > > > > > > > > > > > > > > > > > > > > On Fri, Apr 25, 2008 at 8:53 PM, Rich Collins > > > > > > nilsi2002@gmail.com> wrote: > > > > > > > > > > > > > > > nbma mode on the hub will not help you with dense-mode since > > > > > > > > you don’t have an explicit join. > > > > > > > > > > > > > > > > Maybe one option is to build a pim dense tunnel between the > > > > > > > > two spokes? > > > > > > > > > > > > > > > > -Rich > > > > > > > > > > > > > > > > > > > > > > > > On 4/25/08, Ahsan Mohiuddin > > > > > > > > wrote: > > > > > > > > > > > > > > > > > Hello Group, > > > > > > > > > > > > > > > > > > I have two FR spokes R2 and R4 connected out R5 (hub)’s > > > > > > > > > multipoint sub-if > > > > > > > > > s1/0.245. The network is running PIM sparse-dense. R2 is a > > > > > > > > > client for group > > > > > > > > > 228.22.22.22. There is no RP for it, hence its a > > > > > > > > > dense-mode group. All PIM > > > > > > > > > routers receive ping replies from the 228.22.22.22 client > > > > > > > > > (R2), except the > > > > > > > > > other FR spoke R4. I have already checked for RPF failure > > > > > > > > > but can’t see any. > > > > > > > > > On R5, I can see interface s1/0.245 as being in the (S,G) > > > > > > > > > entry’s Incoming > > > > > > > > > interface list but not in the Outgoing list. I have > > > > > > > > > already added ip pim > > > > > > > > > nbma-mode under this sub-if, but R4 is unable to ping the > > > > > > > > > group. ANy > > > > > > > > > comments are appreciated. P.S. nothing but physical > > > > > > > > > interfaces is allowed on > > > > > > > > > both R4 & R2 (FR spokes). > > > > > > > > > > > > > > > > > > thanks in adv for your inputs > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Pass the CCIE in six weeks, Guaranteed! > > > > > > > > > http://www.certscience.com/CCIE > > > > > > > > > > > > > > > > > > _______________________________________________________________________ > > > > > > > > > Subscription information may be found at: > > > > > > > > > http://www.groupstudy.com/list/CCIELab.html
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