I have a question regarding the typical hub and spoke fram relay configuration. In the Lab that I am currently working on, it was required to configure the HUB router with one PHYSICAL and two LOGICAL (Point to Point) frame-relay links on the Same interface. In other words, there is S0/0-> R3, S0/0.2->R2 and S0/0.4->R4. Now, the catch is that both subinterfaces MUST belong to the same ip subnet. I was able to configure all ip's, pvc's, etc but I noticed that for some reason, either of the spokes cannot ping the HUB even though the FR PVC is up and even OSPF adjacencies are being created between the routers. Also, both spoke routers can ping each other (going through the HUB). So my question is: Why can't I ping from either spoke routers to the HUB but I CAN ping between the spokes and OSPF adjecencies are being formed between the Spokes and Hub? Is there a problem with ICMP protocol in this setting? Can anybody point me to the right direction? The relevant config is pasted below:
I might suggest two solutions to the problems *** the kicker here is the same subnet for both sub-interfaces. This can't be done with one of two solutions below. 1. Use virtual interface on the hub router (this automatically creates virtual-access interface) Ex: Int virtual-template 1 Ip address (use the IP for both S0/0.2 and S0/0.4) ! Int s0/0.2 and 0/0.4 (point-to-point or multipoint) R3(config-subif)#frame-relay interface-dlci xxx ppp virtual-Template 1 (can use broadcast keyword at the end) OR 2. Bridging on hub router Bridge irb ! Bridge 1 protocol ieee Bridge 1 route ip ! Interface s0/0.2 (and same for s0/0.4) frame-relay map bridge xxx (can use broadcast keyword at the end)
