HP T1453-90001 manual Properties of a Vlan

Overview of Installation and Configuration

Properties of a VLAN

Properties of a VLAN

When a VLAN is created on a given LAN card port, (see “Creating a VLAN”), the system generates a virtual PPA or VPPA which can be used to send and receive 802.1Q tagged frames on that LAN card. Each HP-UX VLAN has a Virtual PPA associated with it. A VPPA has essentially the same properties as a physical point of attachment (PPA) on a LAN card. The differences are:

1.A VPPA is associated with a VLAN, the properties of which are determined by the create (or modify) command. The PPA of a physical interface doesn’t have a VLAN associated with it.

2.A VLAN doesn’t have a unique hardware instance. VPPA values are assigned such that they don’t overlap with hardware instance numbers of physical interfaces on the system.

Note: the PPA assigned to a LAN card port is the same as its hardware instance number.

3.A VLAN shares all the link properties of the physical interface on which it is configured. Any changes to the underlying physical interface will be propagated to all its VPPAs.

In the sample lanscan output in the section “Displaying a VLAN and its Properties,” lan5000 shares all the properties (such as speed, duplexity, MTU, MAC address) of the physical port with which it is associated, lan0.

4.All frames transmitted via a VPPA are VLAN tagged. Frames transmitted via a physical PPA are sent untagged.

5.lanadmin non-interactive mode options to set the value of MTU (-M), speed (-S or -X), station address (-A) and reset the MTU (-R) and interactive mode options “reset” and “special” are not supported for VPPAs.

6.lanadmin interactive mode displays and clears driver statistics for VPPAs.

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