4108gl lost packets between c7000

[jdixon]

I'm having an issue with a switch module that i'm losing packets on. Weird thing is it only seems to be one module.

Basically I have one core switch and two c7000 enclosures that have 2 GBE2c modules in each enclosure. I have a trunk consisting of 2 x 1GB connections from the core switch to each module in the enclosure.

Each enclosure also has an interconnect between the modules internally.

Spanning tree is turned on the core switch and each module in the enclosure. I have compared the configurations between the working enclosure and the not working enclosure and they appear to match up, but I'm experiencing an issue with only one module on the enclosure on the right?

Attached is a picture of the setup.

Is there something else I should be doing different? I am using VLANS and have all the trunks tagged for all the VLANS(including the interconnect links between the modules internal to the enclosures

[jdixon]

Probably would help if I attached the picture lol

[paulgear]

Hi jdixon,

If you've compared the configurations and are confident that you've eliminated any inconsistencies, then hardware seems the most likely cause; either the module itself, or the cables/connectors.

[jdixon]

The two modules were not in use for about a year. I then got them and flashed them to the latest firmware. The problem only exists with one module.

So I will try to reflash it as well as make sure the cables are good.

Let me ask you this... since I have a trunk between them with 2 links, if one of the links is bad would that cause this? The trunk tearing down and rebuidling when the one link connects and disconnects? I did try to watch the switches to see if it reported any disconnects on the two ports but didn't see anything.

[paulgear]

I definitely think one link bad in an LACP trunk could cause you to end up with dropped packets.  I would try running with just one of them for a while, then try switching over to the other one.