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New Member

Private VLAN - trunking to a 2900XL switch

I have a 6500 which understands Private VLANs and a 2924C which does not. They are connected together via a 802.1q trunk. Normal VLANs run across them fine.

The problem is when I use private VLANS. I have the following VLANS:

10 - primary

11 - isolated

12 - community

Now all the hosts on the 6500 behave as expected and see what they are supposed to see. A host on the 2924C on the primary VLAN (10) can only see the promiscuous hosts on the 6500. They do not see anything from isolated or community ports but they can see anything on promiscuous ports.

This is probably a sensible default. Is there any way of making the trunk port promiscuous?


Re: Private VLAN - trunking to a 2900XL switch


It is working as expected. Any host can talk to a host in promiscous mode, but not on isolated or community port.

New Member

Re: Private VLAN - trunking to a 2900XL switch

Replying to my own post, but it might be useful for others.

The simple answer is you cannot do it.

The more complicated one is you can with a Cat 4000, it has the right commands. The 6500, while being a more modern bit of gear, only has half the commands.

For Cat4000 owners, you can do it with the switchport mode private-vlan trunk command.