[c-nsp] Weird Routing Behaviour

[Lin Domingo]

I am having weird routing issues with the T1 circuits. We use /30 subnets for all T1 circuits, so for customer X with assigned subnet of  x.x.x.176/30, x.x.x.177 is the serial interface on the ISP end of the circuit. The ISP side of the router is defined thusly:

interface Serial6/0/16:0
 description  XYZ Customer
 ip address x.x.x.177  255.255.255.252
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 encapsulation ppp
 no cdp enable


Now, I am noticing some weird behaviour:

(a.) For some reason, the router can not ping (its own) ip  -x.x.x.177 -configured on the serial interface! 
(b.) Same router can ping the CPE end of the circuit, in this case, x.x.x.178. '
(c.) Also, if the circuit is bonded multilink T1, the router can ping its own ip, but even then, a traceroute to that IP shows that the router travels to its own IP by way of the CPE ip!! When pinging its own ip, the response time is about 4ms!  When pinging that same ip from a neigbhouring router, response time is 1ms!


Now, if I do a "show ip route  ip address x.x.x.177", I get:

Routing entry for x.x.x.128/25
  Known via "static", distance 1, metric 0 (connected)
  Redistributing via eigrp 12125
  Advertised by eigrp 12125
  Routing Descriptor Blocks:
  * directly connected, via Null0
      Route metric is 0, traffic share count is 1



Why is the route showing as "directly connected, via Null0"  instead of "* directly connected, via Serial6/0/16:0"  ? Again if the circuit is a bonded multi-link t1, the route shows up correctly as "* directly connected, via Multilink10"


Am I missing something? Someone help please!


Dominic