[c-nsp] VLANs over IP unnumbered

[Manaf Oqlah]

Hi All,

I have a very strange problem here. I have Cisco 7600 router connected to
several ME3750 switches with trunks. the 7600 router configured with VLANs
over IP unnumbered SVI interfaces. Each L2 VLAN on 7600 router represent the
clients on each switch and the SVI interfaces are configured with ip
unnumbered command pointing to the main SVI interface (the gateway for
clients).

the problem is when i am attempting to execute the command "show ip route
10.10.10.10"  {10.10.10.10 is a client} firstly i got the below result:

Routing entry for 10.10.10.10/32
  Known via "static", distance 1, metric 0 (connected)
  Routing Descriptor Blocks:
  * directly connected, via Vlan501 -------------> Vlan501 is the client
vlan
      Route metric is 0, traffic share count is 1


Suddenly after a while i execute the same command and i got the below result
and the client will be unreachable:

Routing entry for 10.10.0.0/20
  Known via "connected", distance 0, metric 0 (connected, via interface)
  Routing Descriptor Blocks:
  * directly connected, via Vlan111 -------------> Vlan101 is the main vlan
on 7600 router which has the ip address 10.10.10.1 (clients gateway)
      Route metric is 0, traffic share count is 1

What could be the problem?? is it a bug on 7600 router or something else?!!

Thank you,
Manaf