[c-nsp] Fiber issue, banging my head.

[Drew Weaver]

Hi there.

We are trying to connect a Catalyst 6509 connected via fiber to two GSR 12000 routers.

When we connect the switch to the router(s) via G5/1 and G5/2 (on the Supervisor 720) we get input errors on the Router (the GSR side), the line goes up/up but we see:

Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
 1668 input errors, 1668 CRC, 0 frame, 0 overrun, 0 ignored

The throughput between the two pairs is also terribly slow.

We have tried different cards in the GSRs, we have tried different fiber cables.

The configurations are very simple:

--Pair #1--
Cat side:

interface GigabitEthernet5/1
 description Gig-E to GSR #1
 ip address 192.168.0.34 255.255.255.252
end
GSR side:
interface GigabitEthernet6/0
 description Gig-E to Catalyst 4
 ip address 192.168.0.33 255.255.255.252
 no ip directed-broadcast
 negotiation auto
end

--Pair #2-
Cat side:
interface GigabitEthernet5/2
 description Gig-E to GSR #2
 ip address 192.168.0.106 255.255.255.252
end
GSR side:
interface GigabitEthernet6/0
 description Gig-E to Catalyst 4
 ip address 192.168.0.105 255.255.255.252
 no ip directed-broadcast
 negotiation auto
end

we have 3 other catalysts connected to these two GSRs in a similar fashion (exactly the same) and the GSRs do not show errors.

Any idea why the errors would only show on the GSR side?

Thanks for any advice.

-Drew