HP-UX 11i Version 1 Installation and Update Guide, June 2004

Configuring Built-In PCI Networking

1000Base-T (Gigabit Ethernet)

Appendix D206

Optional Step: Configure Jumbo Frame Size (Jumbo

Frames only supported at 1000 Mbit/s)

Jumbo frames have an mtu_size of 9000 bytes. If using Jumbo Ethernet

frames, ensure that all end stations on a given LAN (that is, no routers

or layer 3 switches in between) have the same MTU setting. However

switch ports in the LAN can have any MTU setting greater than or equal

to the end station MTU.

1. Obtain the PPA number of the card by executing: lanscan

2. Choose one of two configuration methods that will permanently save

your configuration. You can either:

• use the GUI-based system admin manager (SAM).

To use SAM, type sam at the HP-UX system prompt; then

double-click Networking and Communications, and then

Advanced Configuration--see the Ethernet Support Guide for

details, and then do the steps for verifying the MTU size;

• edit the configuration file in /etc/rc.config.d/using an editor

such as “vi.” Depending on your driver, the filename can be

either hpgelanconf, hpigelanconf, or hpietherconf.

Set the mtusize by editing either

HP_GELAN_MTU[0]=mtusize,

HP_IGELAN_MTU[0]=mtusize, or

HP_IETHER_MTU[0]=mtusize, and insert the proper interface

name: HP_GELAN_INTERFACE_NAME,

HP_IGELAN_INTERFACE_NAME, or

HP_IETHER_INTERFACE_NAME. When the system reboots,

the interface will be configured for jumbo frame operation.

3. Verify MTU change by executing: netstat -rn. If MTU has not

changed, execute the following commands:

ifconfig lan PPA_number unplumb

ifconfig lan PPA_number ip_address netmask netmask up

4. To check (or verify) the current Ethernet frame size, execute:

lanadmin -m PPA_number