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VLAN traffic across a 3com Unified and 4500

VLAN traffic across a 3com Unified and 4500

VLAN traffic across a 3com Unified and 4500

Short version:

Setup VLAN 5 on a Unified switch and setup VLAN 5 on a 4500.  Plugged cable in on untagged port from each.  Devices can only communicate with devices on the same unit on the same vlan.  Vlan does not cross to the other switch with the same vlan.

Long Version:

I have the 3com Unified switch that I use to service my internal wireless clients (Employee network) and also guest access on "Guest Network".  I had my internal clients wirelss on the default VLAN 1 while the Guest access is on VLAN 10.

Ports 21 - 24 had the WAPs on them and tagged. Ports 19 and 20 are configured as untagged ports for VLAN 10 and attached to Port 19 was a firewall that would also serve DHCP addresses for VLAN 10 (the guests).  This works fine.  Guests go right out to the Internet.

Previously I had the internal Employee wireless part set to the default VLAN 1 with ports 1-18 set to untagged.  Port 1 of the Unified was plugged into a 3Com 4500 port also on the default VLAN1 and all the wired and wireless devices could communicate between the switches (except for the isolated VLAN 10 of course)

The employee network is growing and I now have to subnet it so I added VLAN 5 for the wireless client, changed the Employee wireless settings to VLAN 5 and changed port 17 and 18 to untagged ports for VLAN 5.  I also configured a VLAN 5 on the 4500 and set ports 29-48 to be on VLAN 5.  I plugged a port from VLAN 5 on the Unified into a port on VLAN 5 on the 4500 however devices from the two units are not able to communicate across units.

RE: VLAN traffic across a 3com Unified and 4500

The ports connecting the unified and the 4500 need to be tagged for VLAN 5.  The other "client access" ports on either switch would be untagged access for VLAN 5.

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