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New Member

Cisco Switch 2950 Multi-VLAN Configuration

Anyone can help me configuring one single port to have access on MULTI-VLAN within the same switch.I am having switch Cisco 2950 12 port Standard Image IOS: IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(13)EA1, RELEASE SOFTWARE(fc1)

VLAN 100 active Fa0/1, Fa0/2, Fa0/3

VLAN 101 active Fa0/1, Fa0/4, Fa0/5, Fa0/6

VLAN 102 active Fa0/1, Fa0/7, Fa0/8, Fa0/9

VLAN 103 active Fa0/1, Fa0/10 Fa0/11 Fa0/12




Re: Cisco Switch 2950 Multi-VLAN Configuration

What is port Fa0/1 being used for? You could configure it as a trunk (ISL or 802.1q) or if you want to use a network analyzer/sniffer you could configure the "port monitor" command.



New Member

Re: Cisco Switch 2950 Multi-VLAN Configuration

This Fa0/1 port has been used to have commection to Fast Ethernet Port of the Cisco Router.

I need every VLAN of this switch to have access to Cisco Router.



New Member

Re: Cisco Switch 2950 Multi-VLAN Configuration

In this case you have to configure a switch port trunk, line patrick says. A trunk port can manage a traffic for multiple Vlans.

The commands on the switch are:

Switchport mode trunk

Switchport trunk encapsulation do1q

In the case that you are going to configure the trunk with the dot1q encapsulation.

In side of the router you only have to configure the Sub-interface and their respective Vlan. For example.

Interface Fastethernet0/0

Interface Fastethernet0/0.1

encapsulation dot1q 10

Where 10 is the vlan number on the switch.

New Member

Re: Cisco Switch 2950 Multi-VLAN Configuration

In the scenario, where if there is no Router connect to Switch & configuration like this:

VLAN100 ---- Fa0/1, Fa0/2, Fa0/3, Fa0/4, Fa0/5

VLAN101 ---- Fa0/1, Fa0/6

VLAN102 ---- Fa0/1, Fa0/7

VLAN103 ---- Fa0/1, Fa0/8

VLAN100 needs to have access to all VLAN (ie, VLAN101, VLAN102, VLAN103), but VLAN101 should not have access to VLAN102, VLAN103 simillarly VLAN102 should also not have access to VLAN101, VLAN103 and so on.



New Member

Re: Cisco Switch 2950 Multi-VLAN Configuration

The features you are looking for is possible with PVLAN (Private VLANs)

However 2950 does not support all the features of PVLANs at present, though it may support in future.

(Pls refer:

Where as your requirement can be fullfilled, if you use a router/L3 device,trunk all the L2 VLANs to L3 device for inter VLAN routing and restrict traffic flow from one VLAN to the other using packet filtefing at the L3 interface.