Mac-address table entry not removing

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Nov 16th, 2007
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I have a VMware server with a teamed NIC. Each NIC is connected into a separate Cat 6513 switch.

The 2 6513s are connected to each otehr via a Layer 2 etherchannel trunk and all vlans are trunked across this.

In normal operation, the VMWare servers' Mac-address is seen via the connected port on router A. When we shut down this port, the mac-address moves to the connected port on router B as is to be expected.

Here's the problem.

When we re-enable the 1st port, the MAC-address is now seen via both ports and we have connectivity issues.

To add to the confusion, if spanning-tree is enabled on these ports, everything works correctly and the mac-address moves back.

With spanning-tree portfast enabled (as recommended by vmware) we get this problem. To resume connectivity we have to manually clear the mac-address table entry from router b.

Also, note, these ports are trunk ports so we use the "spanning-tree portfast trunk" command to enable portfast.

Any ideas ?



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xcz504d1114 Fri, 11/16/2007 - 08:57
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We had similar problems, ended up creating a broadcast storm in the end. Our problem ended up being the software used to team the NIC's on the server. I don't remember if we were using the built in microsoft or third party software, but one of them caused the problem.

Good luck in finding your issue.


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