-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Lin Domingo Sent: den 13 augusti 2010 05:47 To: [email protected] Subject: [c-nsp] Weird Routing Behaviour
>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 Do you have a static /25 pointing to null 0 like a pull down route? Is your /30 part of this /25? Seems weird that you won't see your /30 in the routing table. I have also had the experience of not being able to ping a serial interface I'm not sure why this is but maybe someone has a good explanation for it. /Daniel _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
