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Automatic pruning not working

I have 2 6509s and a 6513 trunked with gig etherchannels. The 6509 in the middle also has closets of 3500XL stacks off of it and it is running dual MSFCs with the routers in hot standby for the gateway address of each VLAN. When it was installed the 3500s did not support automatic pruning so I manually pruned those trunks. Now that the new 6509 and 6513 have been added I expected automatic pruning to happen on their trunks to the central 6509 but it is not. When I watch the trunk with a sniffer I see IPX and IP broadcasts from all VLANs even though there are only a few on the new switches and no routing in those switches. Anyone have any ideas whats wrong?


Re: Automatic pruning not working

Since there has been no response to your post, it appears to be either too complex or too rare an issue for other forum members to assist you. If you don't get a suitable response to your post, you may wish to review our resources at the online Technical Assistance Center ( or speak with a TAC engineer. You can open a TAC case online at

If anyone else in the forum has some advice, please reply to this thread.

Thank you for posting.

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