The goal of this article is to show inter-operable trunk port configurations for Cisco and 3com SuperStack III switches. This information will specifically focus on connecting a Cisco switch to a 3com switch and establishing an 802.1q trunk.

Goal:

Workstations configured for vlan 10 and Servers configured for vlan 11 are connected to a Cisco Switch. Another switch has to be added for capacity reasons, however it is a 3com. Additional Workstations and Servers need to be connected to the new 3com switch, using the same vlan separation configured on the Cisco access switch. The workstations in vlan 10 must communicate to each other across both switches. The Servers must also communicate across switches, which are in vlan 11.

In this example:

• The Cisco switch is connected to the 3com switch using port 1 on each side.
• Create two vlans locally on each switch
  • Vlan 10 (for Workstations)
  • Vlan 11 (for Servers)
• Configure port 1 on each switch for 802.1q trunking

Cisco switch configuration:

vlan 10
 name Workstations
vlan 11
 name Servers

interface FastEthernet0/1
description Connected to 3com switch
switchport trunk encapsulation dot1q
switchport mode trunk

interface FastEthernet0/2
description Workstation
switchport access vlan 10

interface FastEthernet0/3
description Server
switchport access vlan 11

3com SuperStack III configuration steps:

Select menu option (bridge/vlan): create
Select VLAN ID (2-4094)[3]: 10
Enter VLAN Name [VLAN 10]: Workstations

Select menu option (bridge/vlan): create
Select VLAN ID (2-4094)[3]: 11
Enter VLAN Name [VLAN 11]: Servers

Select menu option (bridge/vlan/modify): add
Select VLAN ID (1-2,116,120)[1]: 10
Select bridge ports (AL1-AL4,unit:port...,?): 1:2
Enter tag type (untagged, tagged): untagged

Select menu option (bridge/vlan/modify): add
Select VLAN ID (1-2,116,120)[1]: 11
Select bridge ports (AL1-AL4,unit:port...,?): 1:3
Enter tag type (untagged, tagged): untagged

Select menu option (bridge/vlan/modify): add
Select VLAN ID (1-2,116,120)[1]: 10-11
Select bridge ports (AL1-AL4,unit:port...,?): 1:1
Enter tag type (untagged,tagged): tagged