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New Member

C2924XL trunk port connected to server

We have a switch used for connecting client servers to our backup server - Historically all ports have been in the one vlan.

Is it possible to have ports clients are connected to in seperate vlans, and the port that connects to the backup server in trunk mode and still allow access to the backup server? (i.e. so clients would not be able to 'see' other clients servers, but could still access the backup server)

All servers would be in the same subnet (



interface FastEthernet0/20

switchport access vlan 2

spanning-tree portfast


interface FastEthernet0/21

switchport access vlan 3

spanning-tree portfast



interface FastEthernet0/22

switchport access vlan 4

spanning-tree portfast


interface FastEthernet0/23

switchport access vlan 5

spanning-tree portfast



interface FastEthernet0/24

switchport trunk encapsulation dot1q

switchport mode trunk


switchport trunk allowed vlan all was also enabled on FE0/24

I have tried the above without success.

If I place FE0/24 trunk native vlan 3, then client on FE0/21 can successfully access the Backup Server.

Any assistance is greatly appreciated.



New Member

Re: C2924XL trunk port connected to server

The only way that is going to work is if your NIC understands 802.1q and that is not going to happen with a standard NIC. The alternative is routing between VLANs which is probably not what you want to do.

What you might want to use is Private VLANs, these are a standard way of preventing access ports, in the same VLAN, from talking to each other but still being able to reach, pre-configured, shared ports. Not too sure what 2924 support is for PVLANs but should be easy enough to check.