I have run into an interesting issue with a trunked connection to my ASA.
Scenario: ASA-5510 connected to a Catalyst 3524 switch via a dot1q trunk. There are approximately 12 vlans configured and passing traffic.
The ASA interface shows no errors; the Catalyst switch is incrementing runts fairly rapidly.
From what I have read this typically is a cabling or hardware issue. We changed ports and cables on the Catalyst switch to rule out that side. Both ASA and Switch are set to Full Duplex/ Speed 100.
From a troubleshooting perspective, I am limited on my packet captures due to the switch and/or my NIC hardware discarding 'bad' packets. I don't have access to a hardware packet capturing device or a NIC with that capability.
To anyone's knowledge, is there a way to capture the packets being dropped at the switch port? I have a port monitor set up and have disabled "checksum offloading" on my NIC; so far that is the best I have come up with.
It looks like the switch will increment the runts counter, but not log any of that info.
I am eliminating any other port issues I see on the switch, but that hasn't made a difference so far.
My apologies for the long post, but I do appreciate your patience and expertise!
Thanks for your time!