I did a VMware ESX project last week at a client that has HP ProCurve switches. I had worked a little with HP ProCurve switches in the past so I knew the terminology that HP uses is different than what Cisco uses.
Cisco vs. HP terminology:
- Cisco – Trunk links provide VLAN identification for frames traveling between switches and Trunks carry traffic from all VLANs to and from the switch by default but can be configured to carry only specified VLAN traffic. Cisco switches have two Ethernet trunking mechanisms: ISL and IEEE 802.1Q. VMware supports only 802.1Q. To configure a switch port as a trunk you would issue the commands
“switchport mode trunk”
“switchport trunk encapsulation dot1q”
To allow only specific VLANs to be trunked you would issue the command
“switchport trunk allowed vlan” and type in the VLANs to allow.
- HP – A trunk is a method of combining (aggregating) 2 or more switch ports to get more bandwidth between two switches. This is what Cisco calls Port Channeling or Etherchannel. To do the equivalent to of the Cisco trunk you would tag the switch ports connected to the ESX host with the VLANs that need to be “trunked”. Here is a screen shot of the VLAN configuration page of an HP ProCurve switch. Ports 1 and 2 are connected to an ESX host. Notice how ports 1 and 2 are tagged for VLAN 100 and untagged for VLAN 1. VLAN 1 is untagged because it is the default VLAN.
- Cisco – To assign a switch port to a VLAN on a Cisco switch you would use the command “switchport access vlan 10”
- HP – To assign a switch port to a VLAN on and HP switch you would untagg that port in the specified VLAN.
Here is a link to another blog post from Scott Lowe where he is discussing the same thing.