Category Archives: voip

Voice VLANs on HP Networking

In order to configure voice vlans, we need to play around with trunks and vlan tags. However, one may be surprised to find that on H3C HP hardware, there are three port link types:

  • Access
  • Trunk
  • Hybrid

So what on earth is a hybrid port? In order to answer that question, it is necessary to point out that VLAN classification of frames/packets can be based on the following:

  • Port-based
  • MAC address-based
  • Protocol-based
  • IP-subnet-based
  • Policy-based
  • Other types

Normally, everything happens on port level – depending on the VLAN access port setup, traffic entering a certain port will get classified into the correct VLAN.

A Hybrid port is  a port that can belong to multiple VLANs, can receive or send packets for multiple VLANs, used to connect either user or network devices.

That basically means that a hybrid port can do almost whatever you want it to do. For example, you can assign the port to appear as an access port to a specific MAC address, while still functioning as a trunk, while having a native vlan for untagged traffic. Also, a hybrid port can function as a trunk port with a native vlan.

So, in a nutshell, in order to configure your regular port with tagged vlan for VoIP phones + access vlan for the PC, you can either choose the classic method, or use a hybrid port. Since I presume everybody knows how to do it the old-fashioned way, let us configure it using a hybrid port.

So, what do we need for an IP phone and a PC? A tagged vlan for the Voice packets and an access vlan for the PC. Let us assume that vlan 102 is the Voice vlan, and vlan 7 is the PC vlan.

[HP-KC51-V] interface GigabitEthernet1/0/1
[HP-KC51-V-GigabitEthernet1/0/1] port link-type hybrid
[HP-KC51-V-GigabitEthernet1/0/1] port hybrid pvid vlan 7
[HP-KC51-V-GigabitEthernet1/0/1] port hybrid vlan 102 tagged
Please wait... Done.

[HP-KC51-V-GigabitEthernet1/0/1] stp edged-port enable
Warning: Edge port should only be connected to terminal. It will cause temporary loops if port GigabitEthernet1/0/1 is connected to bridges. Please use it carefully!

[HP-KC51-V-GigabitEthernet1/0/1] poe enable
#May 11 13:38:28:863 2000 HP-KC51-V POE/1/PSE_PORT_ON_OFF_CHANGE:
Trap 1.3.6.1.2.1.105.0.1: PSE ID 4, IfIndex 9437185, Detection Status 3.
#May 11 13:38:30:978 2000 HP-KC51-V IFNET/4/INTERFACE UPDOWN:
Trap 1.3.6.1.6.3.1.1.5.4: Interface 9437185 is Up, ifAdminStatus is 1, ifOperStatus is 1
#May 11 13:38:31:169 2000 HP-KC51-V MSTP/1/PFWD: hwPortMstiStateForwarding: Instance 0's Port 0.9437185 has been set to forwarding state!
%May 11 13:38:31:525 2000 HP-KC51-V IFNET/3/LINK_UPDOWN: GigabitEthernet1/0/1 link status is UP.
%May 11 13:38:31:650 2000 HP-KC51-V MSTP/6/MSTP_FORWARDING: Instance 0's GigabitEthernet1/0/1 has been set to forwarding state.

Of course, we enable stp edged-port (the portfast equivalent), as well as the PoE power for the IP phone. Let us inspect the configuration so far:

[HP-KC51-V-GigabitEthernet1/0/1]display this
#
interface GigabitEthernet1/0/1
port link-type hybrid
port hybrid vlan 102 tagged
port hybrid vlan 1 untagged
port hybrid pvid vlan 7
poe enable
stp edged-port enable
#
return

After inspecting the configuration we can observe that VLAN 1 is still permitted as an untagged vlan. However, the PVID (port vlan id), is set to 7. This may be confusing, so let’s elaborate. The untagged 1 VLAN means that the switch will pass traffic (e.g. broadcasts) from VLAN 1 down this port. The PVID of 7 means that when the switch receives untagged traffic, it will place in in VLAN 7.

Because most device management interfaces are assigned to VLAN 1, it is not a good idea to keep the port a part of this VLAN. So, let us remove the untagged VLAN 1 from the hybrid port.

[HP-KC51-V-GigabitEthernet1/0/1]undo port hybrid vlan 1
Please wait... Done.

[HP-KC51-V-GigabitEthernet1/0/1]display this
#
interface GigabitEthernet1/0/1
port link-type hybrid
undo port hybrid vlan 1
port hybrid vlan 102 tagged
port hybrid pvid vlan 7
poe enable
stp edged-port enable
#
return

Now the port is configured. There, wasn’t that difficult, right? 🙂

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