HP Gigabit Ethernet and 100Base-T Cards manual Optional Step Defining Jumbo Frame Size

OpenVMS Installation

Installing the Adapter

The LAN device characteristics that can be set include speed, duplex mode, flow control, and whether jumbo frames are enabled. The MC LANCP SET DEVICE and LANCP DEFINE DEVICE commands modify these settings.

2.Set the desired characteristics according to the Network Configuration worksheet (see Table 2-1). For example, use this command:

MC LANCP DEFINE DEVICE devname /SPEED=1000 /FULL /AUTONEGOTIATE

Table 2-1	Network Card Configuration Worksheet
	Required		Where to
Data Type	/	Default		Example	Your System
			Configure
	Optional
Station	Built-in	As shown on	not	0x0060b0c4012f
address	and	card	configurable
	cannot be
	changed
Link	Optional	Autonegotiating	LANCP	MC LANCP SET
configuration				DEVICE
				/AUTONEGOTIA
				TE
Link	Optional	Autonegotiating	Hub or	MC LANCP SET
speed/duplex			switcha or	DEVICE/
mode			LANCP	SPEED=1000
				/FULL
MTU	Optional	1518 Bytes	LANCP	MC LANCP SET
(Maximum				DEVICE/JUMBO
Transmission
Unit): Jumbo
Frames
Receive flow	Optional	On	LANCP	MC LANCP SET
control				DEVICE/FLOW

a.The speed configuration of the 1000Base-T can be 10, 100, or 1000 Mbps and is determined by the speed setting of the hub or switch port to which the card is connected. The card automatically senses this speed if autonegotiation is enabled. The card only runs at one speed at a time.

To make any configuration values permanent, enter the values in the LANCP permanent device database.

Optional Step: Defining Jumbo Frame Size

(Jumbo Frames Size (Jumbo frames are supported only at 1000 Mbit/s)

Jumbo frames for the LAN driver on OpenVMS V8.2 have an mtu_size in the range of 1518-8192 bytes.

Jumbo frames are enabled system-wide by setting bit 6 in the system parameter LAN_FLAGS. To enable jumbo frames on individual devices, use the LANCP command SET DEVICE/JUMBO. To disable jumbo frames, use the LANCP command SET DEVICE/NOJUMBO.

To preserve the setting of jumbo frames across boots, when using LANCP, define the setting in the LANCP permanent device database, using the command DEFINE DEVICE/JUMBO.

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