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Odd Network Preformance

I have an interesting issue.  In my network, I have a Cisco 6509 with a WS-SUP720-3B card as my network backbone.  Connected to this, through a VLAN is an uplink to a Cisco 2800 series router that runs a 4xT1 MPLS circuit.  The MPLS circuit is owned and managed by AT&T, is I currently do not have access (none at all).

My Issue:
When I ping the LAN interface from my laptop (plugged directly into the 6500), my pings are always in the triple digits (150-500ms).  When I ping the interface from the 6500 CLI, I get 1ms.

My Setup:
The 6500 has an IP of /24
The router has an IP of /24
I have created a VLAN with IP /24
The uplink on the 6500 is assigned to this VLAN

Things I've checked:
Extraneous routes (none)
The 6500's uplink port counters:
GigabitEthernet1/45 is up, line protocol is up (connected)
  Hardware is C6k 1000Mb 802.3, address is c89c.1d63.60d4 (bia c89c.1d63.60d4)
  MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 1000Mb/s, media type is 10/100/1000BaseT
  input flow-control is off, output flow-control is off
  Clock mode is auto
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input never, output 00:00:07, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 3889000 bits/sec, 435 packets/sec
     59282 packets input, 3832276 bytes, 0 no buffer
     Received 1176 broadcasts (962 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 5 frame, 0 overrun, 0 ignored
     0 watchdog, 0 multicast, 0 pause input
     0 input packets with dribble condition detected
     44105770 packets output, 20803951804 bytes, 0 underruns
     0 output errors, 0 collisions, 3 interface resets
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier, 0 PAUSE output
     0 output buffer failures, 0 output buffers swapped out

interface Vlan250
 ip address

ip classless
ip forward-protocol nd
ip route
ip route
ip route
ip route
ip route
ip route
ip route
ip route
ip route
ip route
ip route
ip route 2
ip route


I don't see anything that screams issue to me (minus the 5 frame errors, and 3 interface resets, but those have been static for some time

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Ohh one other thing, I've also added a second IP address to the VLAN interface ( /24) - My previous L3 switch had this IP address, and we just fully removed it yesterday.  I added that address this morning for any device that may have a static IP address (printers, servers, and a few users)


Could you give the configuration of the 6500 from the uplink port to the router and the access port for your laptop ?

Sounds like a duplex and/or auto-negotiation compatibility issue. Have you tried manually forcing 1000 full/half, 100 full/half, etc, on both ends of the problem link - one end at a time, then both at the same time? I have also seen several cases where Cisco Ethernet ports are just plain incompatible with certain NICs, at a hardware level. This is all assuming you have checked the integrity of the Ethernet cable.