Gigabit-Specific Information

This section provides information that will help administer your Gigabit Ethernet products.

Logging and Auditing

Events are logged with NetTL. This is common to Gigabit Ethernet. The following log files are created by NetTL:

For releases prior to HP-UX 11i: nettl.LOG-00 and nettl.LOG-01
For release HP-UX 11i and later: nettl.LOG000 and nettl.LOG001

See Chapter 4 “Troubleshooting” for more information about NetTL.

Detailed Configuration Information

This section provides additional details on configuring your Ethernet card.

Understanding the Gigabit Ethernet Parameters

Several parameters can be configured using either the lanadmin(1M) command-line interface or the graphical user interface provided by the System Administration Manager (SAM). See “Using the lanadmin Tool with Gigabit Ethernet” for details about using this command. The following parameters can be configured:

Generic Parameters

Ethernet Station Address
The Gigabit Ethernet cards come pre programmed with an Ethernet Station Address in the read-only memory. This cannot be modified. However, the Station Address can also be considered to be the active MAC address. By default, the system uses the factory programmed MAC address that resides in the card’s NIC ROM, but users can change the active MAC address or the working MAC address via the lanadmin command or by using SAM.
Maximum Transmission Unit (MTU)
For Gigabit Ethernet, the MTU setting depends on which driver and which HP-UX release you are using. Jumbo Frames are supported only when the link speed is configured to 1000 Mbit/s. Refer to the following table for a summary of the allowable maximum transmission units for each gigabit Ethernet driver and release.

Table 3-1 Allowable MTU Sizes

	gelan	igelan	iether
HP-UX 11i v1 (11.11)	1500 (standard frame) or 9000 (jumbo frame)	1500 (standard frame) or 9000 (jumbo frame)	Full range = 257 through 9000; jumbo frames = range from 1501 - 9000
HP-UX 11i v2 (11.23)	Full range = 1024 through 9000; jumbo frames = 1501 - 9000	Full range = 1024 through 9000; jumbo frames = 1501 - 9000	Full range = 1024 through 9000; jumbo frames = 1501 - 9000

Link Parameters

Speed, Duplexity and Autonegotiation
The exact steps involved in configuring your Gigabit Ethernet card will vary depending on the type of card you have. The following information should be helpful:
NOTE: Any changes made to your configuration files will not take effect until you reboot the system.
- Ethernet partners are two Ethernet devices which are connected by an Ethernet cable (CAT5 or Fiber). For example, two Ethernet cards connected directly to each other by a cable, or an Ethernet card connected to an Ethernet hub or switch.
- You may set the speed and duplexity for Ethernet partners manually or allow the card to automatically set themselves by turning autonegotiate on. Set the partners according to the Supported Configurations table in Chapter 1.
- Setting the speed and duplexity parameters for 1000Base-T cards is done differently than for 1000Base-SX cards. The following information describes both:
  1000Base-T cards
  To configure the card for autonegotiation, enter the AUTO_ON parameter in the driver configuration file. If your driver is gelan, then the file would be /etc/rc.confi.d/hpgelanconf, and the entry would be:
  HP_GELAN_SPEED=AUTO_ON
  If your driver is igelan, then the file would be /etc/rc.confi.d/hpigelanconf, and the entry would be:
  HP_IGELAN_SPEED=AUTO_ON
  To configure the card manually, enter the appropriate parameter from the table below in the driver configuration file. If your driver is gelan, then the file would be /etc/rc.confi.d/hpgelanconf, and the entry would be:
  HP_GELAN_SPEED= <parameter>
  If your driver is igelan, then the file would be /etc/rc.confi.d/hpigelanconf, and the entry would be:
  HP_IGELAN_SPEED= <parameter>
  Link Speed
  Parameter
  10 Half-duplex
  10hd
  10 Full-duplex
  10fd
  100 Half-duplex
  100hd
  100 Full-duplex
  100fd
  For example, to set a 1000Base-T card to 100 Mbit/s, full-duplex, the configuration file entry would be:
  HP_GELAN_SPEED=100fd
  or
  HP_IGELAN_SPEED=100fd
  1000Base-SX cards
  To configure the card for autonegotiation, enter the 1 parameter in the driver configuration file:
  HP_GELAN_AUTONEG=1
  Since the 1000Base-SX card only works at 1000 Mbit/s, there is no need to set a speed parameter.
  If you wish to disable autonegotiation, you may do so by using the 0 parameter in the driver configuration file:
  HP_GELAN_AUTONEG=0
  This will set the card to no autonegotiation and full-duplex.
Receive flow control
Flow control allows use of flow control negotiation and the sending and receiving of pause frames. When the flow control parameter is on, the card receives and manages pause frames sent by the link partner. When the flow control parameter is off, the card will silently discard these pause frames. The card cannot be configured to send pause frames.
The default value is ON.

Using the lanadmin Tool with Gigabit Ethernet

This section explains the options available in lanadmin to support the Gigabit Ethernet driver and how to use them. The lanadmin(1M) tool is used to display and set parameters, as specified by the following commands:




	NOTE: When your system is rebooted, settings that were made via the lanadmin(1M) command will be lost. To retain configuration settings permanently in the configuration file (`/etc/rc.config.d/hpgelanconf` or `/etc/rc.config.d/hpigelanconf`), use the SAM utility or manually edit the configuration file.

To display the card’s station address, enter:
$ lanadmin -a ppa

To set the card’s station address, enter:
$ lanadmin -A station_addr ppa
In this command, ppa is the Card Instance Number (also known as physical point of attachment or PPA) (for HP-UX 11.0 and later). PPA may be obtained from the lanscan(1M) output.

To get and display settings corresponding to option specified by get_options of the interface corresponding to PPA, enter the following:
$ lanadmin -g get_options
where: get_options is optional and is case insensitive. At present the only allowed value is mibstats.
On the HP-UX 11i v2 release of September 2004, the gelan, igelan, and iether Gigabit Ethernet drivers support 64-bit MIB statistics per RFC 2863 in addition to 32-bit management information base (MIB) statistics.

To display the maximum transmission unit (MTU):
$ lanadmin -m ppa

To set the MTU, enter:
$ lanadmin -M mtu_size ppa

To display the usage information for the interface corresponding to PPA. Also, display the upper level protocols and applications attached to the interface corresponding to PPA. If none attached it prints nothing. To display, enter:
$ lanadmin -p

Executes VLAN specific command:
$ lanadmin -V VLAN_command
See the manpage vlan(7) for complete syntax and usage of the -V option. The supported VLAN commands are: create-Create a VLAN; modify-Modify properties of a VLAN; delete-Delete a VLAN; scan-Get information about all VLANs on a system; info-Get information about a particular VLAN on a system

To verify the change in MTU on all HP-UX operating systems, enter:
$ netstat -in

To display link parameters, enter:
$ lanadmin -x option ppa

To set link parameters, enter:

$ lanadmin -X option ppa
In this command, option specifies the operation to be carried out.

Table 3-2 “Link Card Parameters that lanadmin can Display (-x) or Set (-X) ” lists the parameters that can be set with lanadmin -X or displayed with lanadmin -x.

Table 3-2 Link Card Parameters that lanadmin can Display (-x) or Set (-X)

Option	Setting
help	Lists the -X or -x options
-x card_info	Displays card and driver revision and settings
auto_on	Turns on auto-negotiation mode
auto_off	Turns off autonegotiation mode for a 1000Base-SX
fctrl on	Turns on receive flow control
fctrl off	Turns off receive flow control
-x speed	Displays peed and duplexity of the link
10hd	Sets speed of a 1000Base-T to 10 Mbit/s half-duplex
10fd	Sets speed of a 1000Base-T to 10 Mbit/s full-duplex
100hd	Sets speed of a 1000Base-T to 100 Mbit/s half-duplex
100fd	Sets speed of a 1000Base-T to 100 Mbit/s full-duplex
send_max_bufs*	Sets send buffer coalescing threshold [1 - 128]
recv_max_bufs*	Sets receive buffer coalescing threshold [1 - 256]
send_coal_ticks*	Sets send interrupt coalescing ticks [0 - 10000000]
recv_coal_ticks*	Sets receive interrupt coalescing ticks [0 - 10000000]
stats clear	Clears all driver and card statistics
-x stats drv	Displays all driver and card statistics
-x vmtu <ppa>	Displays the TSO capability of the link. See “Support for TCP Segmentation Offload (TSO)” for details.
-X vmtu new_vmtu_value <ppa>	Sets the TSO vmtu value. See “Support for TCP Segmentation Offload (TSO)” for details.
* These options require the desired value to be specified after the option name. Some of these values may vary due to performance tuning efforts. See “Performance and Tuning Considerations” more information.

Card Information Example

To display the card information, enter:

$ lanadmin -x card_info ppa

*********** Version Information ***********
Driver version: B.11.23.05
Firmware version: 12.4.5
Chip version: 0x6
PCI-XPCI-X Sub-System ID: 0x106f (1000Base-SX)
PCI-X Sub-Vendor ID: 0x103c
Board revision: C
Software Key: 6
Engineering Date Code: B-3845

*********** Card Setting ***********
Driver State: IGELAN_ONLINE
Auto Negotiation: On
Flow Control: On
Send Max Buf Descriptors: 16
Recv Max Buf Descriptors: 1
Send Coalesced Ticks: 1000
Recv Coalesced Ticks: 0

Card Statistics Example:

To display the card statistics, enter:

$ lanadmin -x stats drv ppa




	NOTE: See Appendix D “Card Statistics” for a sample output and explanation of the card statistics.

Send Buffer Coalescing Example:

To display the send buffer coalescing threshold, enter:

$ lanadmin -x send_max_bufs ppa

Send buffer coalescing threshold = 16

Receive Interrupt Coalescing Example:

To display the receive interrupt coalescing ticks, enter:

$ lanadmin -x recv_coal_ticks ppa

Receive interrupt coalescing ticks = 0

Flow Control Example:

To display the flow control setting, enter:

$ lanadmin -x fctrl ppa

Flow control is enabled

Speed Example:

To set the speed to 100 Mbit/s full-duplex on 1000Base-T, enter:

$ lanadmin -X 100fd ppa




	NOTE: The `lanadmin -S` option to set the speed is not supported on Gigabit Ethernet.

Stats Clear Example:

To clear all driver and card statistics, enter:

$ lanadmin -X stats clear ppa

Buffer Coalescing Threshold Example:

To set the send buffer coalescing threshold, enter:

$ lanadmin -X send_max_bufs 32 ppa

Note that the send_max_bufs tuning option requires the additional option 32 (the coalescing threshold).

Interrupt Coalescing Ticks Example:

To set the send interrupt coalescing ticks, enter:

$ lanadmin -X send_coal_ticks 2000 ppa

Note that the send_coal_ticks tuning option requires the additional option 2000 (the number of coalescing ticks).

Performance and Tuning Considerations

The following parameters can be adjusted to improve Ethernet performance:

Send Buffer Coalescing Threshold
Receive Buffer Coalescing Threshold
Send Interrupt Coalescing Ticks
Receive Interrupt Coalescing Ticks




	CAUTION: These features are for advanced users. If you set these parameters and you do not understand what they do, you may have unpredictable results. HP recommends that you use the default settings.

When the card transmits or receives a frame, the system must be notified of the event. If the card interrupts the system for each transmitted and received frame, the result is a high degree of processor overhead. To prevent that, Gigabit Ethernet provides a feature called interrupt coalescence. Effective use of this feature can reduce system overhead and improve performance.

Interrupt coalescence essentially means that the card interrupts the system after sending or receiving a few frames. The number of frames after which the card interrupts the processor can be tuned independently for both send and receive. The tuning can be specified via two parameters each for send and receive, so there is a total of four parameters. One of the two parameters specifies the number of data buffers that the card must transmit (or receive) before interrupting, and the other specifies the amount of time that must elapse before interrupting.

The four tuning parameters are summarized in the following table:

Name	Range	Values	Units
send_max_bufs	1 - 128	16 (for gelan) 10 (for igelan)	# of buffers
recv_max_bufs	1 - 256	1	# of buffers
send_coal_ticks	0 - 10000000	1000 (for gelan) 150 (for igelan)	microseconds
recv_coal_ticks	0 - 10000000	0	microseconds

A send interrupt is generated by the card to the host when either:

The number of buffers sent by the card since the previous send interrupt equals send_max_bufs

or
The time that has elapsed since the previous send interrupt equals send_coal_ticks (a value of 0 disables timer-based interrupt coalescing), and at least one frame has been sent by the controller, whichever occurs first.

A receive interrupt is generated by the card to the host when either:

The number of frames received by the card since the previous receive interrupt equals recv_max_bufs

or
The time that has elapsed since the previous receive interrupt equals recv_coal_ticks (a value of 0 disables timer-based interrupt coalescing), and at least one frame has been received by the controller, whichever occurs first.

For more information, see:

http://docs.hp.com/hpux/netcom/index.html

This site provides detailed information on this topic.