From: alan@BofA.COM (Alan Hobesh)
Subject: Curious ping problem
Organization: Bank of America, Capital Products, RMTG #5906
Date: Wed, 16 Dec 92 22:14:16 GMT

I have a router in San Francisco with two token ring interfaces,
182.9.200.249 255.255.0.0 and 158.67.145.126 255.255.255.128.

When I ping a router in New York with a primary ethernet interface of 192.9.200.220,
255.255.255.0, the ping times out.  
A trace reveals that by changing the source address, the ping succeeds.

The secondary address 147.23.23.2 255.255.0.0 on the ethernet interface 
can always be pinged.

What is going on?

sf-router1#trace
Protocol [ip]:
Target IP address: 192.9.200.220
Source address: 182.9.200.249
Numeric display [n]:
Timeout in seconds [3]:
Probe count [3]:
Minimum Time to Live [1]:
Maximum Time to Live [30]:
Port Number [33434]:
Loose, Strict, Record, Timestamp, Verbose[none]: v
Loose, Strict, Record, Timestamp, Verbose[V]:
Type escape sequence to abort.
Tracing the route to KARLPC (192.9.200.220)
 
  1 158.67.171.125 144 msec 140 msec 140 msec
  2 KARLPC (192.9.200.220) 140 msec 144 msec 140 msec
sf-router1#trace
Protocol [ip]:
Target IP address: 192.9.200.220
Source address: 158.67.145.126
Numeric display [n]:
Timeout in seconds [3]:
Probe count [3]:
Minimum Time to Live [1]:
Maximum Time to Live [30]: 10
Port Number [33434]:
Loose, Strict, Record, Timestamp, Verbose[none]: v
Loose, Strict, Record, Timestamp, Verbose[V]:
Type escape sequence to abort.
Tracing the route to KARLPC (192.9.200.220)

  1 158.67.171.125 140 msec 140 msec 144 msec
  2  *  *  *
  3  *  *  *
  4  *  *  *
  5  *  *  *
  6  *  *  *
  7  *  *  *
  8  *  *  *
  9  *  *  *
 10  *  *  *
Destination not found inside max TTL diameter.

Routing tables follow:

sf-router1#sh ip route
 
Codes: I - IGRP derived, R - RIP derived, H - HELLO derived, O - OSPF derived
       C - connected, S - static, E - EGP derived, B - BGP derived
       * - candidate default route, IA - OSPF inter area route
       E1 - OSPF external type 1 route, E2 - OSPF external type 2 route
 
Gateway of last resort is not set

I    192.9.201.0 [100/8576] via 158.67.171.125, 0:01:20, Serial0
I    192.9.200.0 [100/8576] via 158.67.171.125, 0:01:20, Serial0
I    147.23.0.0 [100/8576] via 158.67.171.125, 0:01:20, Serial0
C    182.9.0.0 is directly connected, TokenRing1
C    158.67.0.0 is subnetted (mask is 255.255.255.128), 7 subnets
I       158.67.155.0 [100/8576] via 158.67.171.125, 0:01:20, Serial0
I       158.67.153.0 [100/10539] via 158.67.171.125, 0:01:20, Serial0
I       158.67.157.0 [100/8726] via 158.67.171.125, 0:01:20, Serial0
C       158.67.147.0 is directly connected, TokenRing2
C       158.67.145.0 is directly connected, TokenRing0
C       158.67.171.0 is directly connected, Serial0
I       158.67.164.0 [100/8726] via 158.67.164.126, 0:01:10, Serial1

ny-router>sh ip route

Codes: I - IGRP derived, R - RIP derived, H - HELLO derived, O - OSPF derived
       C - connected, S - static, E - EGP derived, B - BGP derived
       * - candidate default route, IA - OSPF inter area route
       E1 - OSPF external type 1 route, E2 - OSPF external type 2 route

Gateway of last resort is not set

S    192.9.201.0 [1/0] via 192.9.200.220
C    192.9.200.0 is directly connected, Ethernet0
C    147.23.0.0 is directly connected, Ethernet0
I    182.9.0.0 [100/8726] via 158.67.171.126, 0:01:08, Serial1
C    158.67.0.0 is subnetted (mask is 255.255.255.128), 7 subnets
C       158.67.155.0 is directly connected, Ethernet0
I       158.67.153.0 [100/8539] via 158.67.153.126, 0:01:19, Serial0
C       158.67.157.0 is directly connected, TokenRing0
I       158.67.147.0 [100/8726] via 158.67.171.126, 0:01:08, Serial1
I       158.67.145.0 [100/8726] via 158.67.171.126, 0:01:08, Serial1
C       158.67.171.0 is directly connected, Serial1
I       158.67.164.0 [100/10726] via 158.67.171.126, 0:01:08, Serial1