Ethernet Support Guide (for HP-UX 11i v1, 11i v2)

Installation and Configuration
Manual Speed and Duplex Mode Configuration
Chapter 2
33
Manual Speed and Duplex Mode Configuration
HP PCI-X Ethernet cards support both half- and full-duplex operation. Full-duplex mode
is most commonly found in 10 Mbit/s, 100 Mbit/s, or 1000 Mbit/s switches. Full-duplex
mode may provide a throughput advantage under some circumstances, but the degree of
the advantage is application-dependent.
The Gigabit Ethernet cards also support autonegotiation; so you should not normally
need to manually set the duplex mode. If a card is connected to a device, such as a
switch, that is autonegotiating, the card will autonegotiate with the device to mutually
determine the highest possible speed and duplex settings between them.
If a switch operating at full-duplex mode does not autonegotiate, the card defaults to
half-duplex when autonegotiation is turned off -- this could cause a mismatch between
the card and switch (at either 10, 100 or 1000 Mbit/s). To fix this, use the system admin
manager (SAM) or edit the configuration files to permanently save your settings. You can
use the lanadmin -X command as described later in this section though your changes
would not be saved across reboots.
Ensure that the speed, duplex mode, and autonegotiation of the associated switch are
configured according to the table of Supported Configurations in chapter 1. If the switch
supports autonegotiation on the ports connected to the cards, this should be enabled as
explained in the “Autonegotiation and Autosensing” section.
To determine the speed and duplex mode of your card before performing manual
configuration, enter:
$ lanadmin -x ppa
The ppa is the physical point of attachment. You can get the ppa from the output of the
lanscan command.
To manually set the duplex mode of the interface, use the -X option (NOTE the
uppercase X) of lanadmin as follows:
$ lanadmin -X mode ppa
In these commands, mode can be any one of the following strings (and the fd or hd are
case-insensitive):
10fd =10 full-duplex
10hd =10 half-duplex
100fd =100 full-duplex
100hd =100 half-duplex
To turn autonegotiation on, enter:
$ lanadmin -X auto_on ppa
For example, if the ppa of the 100Base-TX interface is 5, the command to set the card to
10 Mbit/s and full-duplex mode would be:
$ lanadmin -X 10fd 5
After entering the lanadmin -X command, you must wait at least 11 seconds before
attempting to use the specified network interface.