This should be pretty close...

 

vlan database
vlan 2-21
exit
interface ethernet e2
switchport mode general
switchport general allowed vlan add 2 untagged
switchport general pvid 2
exit
interface ethernet e3
switchport mode general
switchport general allowed vlan add 3 untagged
switchport general pvid 3

repeat that for the different ports - change the vlan info for each one

Then, for the "shared" port...

interface ethernet e1
switchport mode general
switchport general allowed vlan add 2-21 untagged

interface range ethernet 1/e1-5

gives invalid parameter error ??

I have tried both methods and neither allow me to ping to the box that should be seen by all machines.
Any ideas ??

Thanks

With "Port Overlapping", I am assumming you are sending traffic from multiple VLANs, untagged, to a single destination usually a system or a router.  Please keep in mind that this can potentially add overhead and is not as secure as standard VLAN segmentation in that the traffic from one VLAN may still be seen by other VLANs.  This is not an ideal way to configure VLANs, however, it is understood that sometimes resources are limited.

Essentially, the 'Access' ports will be members of (2) VLANs and the PVID configured for the unique VLAN (opposed to the 'Common' VLAN).  The interface that has the destination will be configured in ALL VLANs with the PVID configured for the 'Common' VLAN.  This will achieve true port overlapping.  You will need to configure the interfaces as General Mode ports.  Below is an example on how to start the configuration.

console# config
console(config)#  vlan database
console(config-vlan)# vlan 2-50
console(config)# interface range ethernet e1-48
console(config-if)# switchport mode general
console(config-if)# exit
console(config)# interface ethernet e1
console(config-if)# switchport general allowed vlan add 2,50 untagged
console(config-if)# switchport general pvid 2
console(config)# exit
console(config)# interface ethernet e2
console(config-if)# switchport general allowed vlan add 3,50 untagged
console(config-if)# switchport general pvid 3
console(config-if)# exit
..........
console(config)# interface ethernet e48  <- This is the 'Common' Port
console(config-if)# switchport general allowed vlan add 2-50 untagged
console(config-if)# switchport general pvid 50

Hope this helps.

Message Edited by DELL-Randy on 08-02-2005 02:04 PM

Unfortunately this does not seem to work either.
i am unable to ping the external router from either vlan

any other sugestions ?

Thanks all for your help

Please post a copy of your current configuration.

interface ethernet g3
switchport mode general
exit
vlan database
vlan 2,100,200
exit
interface ethernet g3
switchport general pvid 2
exit
interface ethernet g3
switchport general allowed vlan add 100
exit
interface ethernet g3
switchport general allowed vlan add 200
exit
interface vlan 2
ip address 192.168.1.250 255.255.255.0
exit
ip default-gateway 192.168.1.254
Default settings:
Service tag: GY10L71

SW version 1.0.0.112 (date 20-Jun-2005 time 22:04:47)

Fast Ethernet Ports
==========================
no shutdown
speed 100
duplex full
negotiation
flow-control off
mdix auto
no back-pressure

Gigabit Ethernet Ports
=============================
no shutdown
speed 1000
duplex full
negotiation
flow-control off
mdix auto
no back-pressure

interface vlan 1
interface port-channel 1 - 8

spanning-tree
spanning-tree mode STP

qos basic

Your issue is with the VLAN/PVID configuration.  I assume that you want interface ethernet g3 to be members of VLANs 2,100, and 200.  The VLAN IDs will need to include all three tags.  If you want ethernet g3 to be a member of VLAN 2 and any other required VLANs, add the required IDs.  Then assign the PVID of 2 (or the respective VLAN) to make the port a "member" of VLAN 2.

The VLAN IDs will delegate the Egress Rule for traffic.  In that traffic leaving the configured interface may be forwarded to each of the respective VLANs (this is where your security becomes an issue).  The PVID will delegate the Ingress Rule for traffic.  In that traffic received untagged will automatically assume the VLAN ID of the configured PVID, thus can receive traffic from the configured PVID.

Please review the configuration I posted before and attempt to configure the required VLAN IDs and PVIDs as depicted.