Chapter 3. Fibre Channel Option Board Cabling

The storage options use either copper or optical cable of various lengths, as summarized in Table 3-1.

Table 3-1. Cables for Fibre Channel Storage Options

Material

Length

Marketing Code

Part Number

Included/Optional

Use

Copper

10 m (32.8 feet)

X-F-COP-10M

018-0570-001

Included in option;
one per port

Option board to enclosure

Copper

25 m (82 feet)

X-F-COP-25M

018-0571-001

Optional

Option board to enclosure

Optical

25 m (82 feet)

X-F-OPT-25M

018-0656-201

Optional

Option board to enclosure

Optical

100 m (328 feet)

X-F-OPT-100M

018-0656-301

Optional

Option board to enclosure

Optical

300 m (984 feet)

X-F-OPT-300M

018-0656-401

Optional

Option board to enclosure

In the Silicon Graphics fibre storage implementation, copper cable is standard and optical is optional. Two 10-meter copper cables are shipped with the Fibre Channel XIO option board; one is shipped with the Fibre channel PCI option board.


Note: Copper cables longer than 10 meters must be equalized.

This chapter describes cables for the Fibre Channel XIO and PCI option board, both optional and those included in the shipment:

Cable Characteristics

Table 3-2 summarizes characteristics for the copper twinax and fiber optic cables.

Table 3-2. Cable Characteristics

Characteristic

Copper Twinax

Fibre Optic

Variant

100-TW-EL-S full-duplex (quad conductor)

100-M5-SL/N-I

Range

25 meters maximum;
> 10 meters requires equalization

300 meters maximum

Transmitter

PECL

Optical laser
780 nm

Medium

150 ohm

62.5 micron

Range

25 meters

300 meters

Connector

Male DB9

SC duplex connector

Maximum length

Enclosure to server: 25 m

Enclosure to server: 300 m



Caution: To maintain acceptable quality and signal integrity, use only Silicon Graphics-supplied copper and optical cables with your fibre enclosures.


Cable Distances and Shielding

This section discusses each type of FC cable in more detail, including allowable distances.

For information on cabling Silicon Graphics fibre channel storage options to the Fibre Channel XIO or PCI board, see the Origin FibreVault and Fibre Channel RAID Owner's Guide. In the case of Origin2000 and Onyx2 systems, only qualified Silicon Graphics support personnel install the boards and cable the options.


Caution: If a host system and a fibre channel enclosure are on separate building grounds, grounding problems may arise when this cabling is connected with a copper cable utilizing a DC ground shield on both ends. In this case, use the optional fibre optical cabling to link host and enclosure.


Copper Cable Distances and Shielding

The copper twinax cable is a fully shielded, full-duplex, balanced cable capable of supporting distances of 25 meters at the 1.0625 Gbaud transfer rate. The connectors for both ends of the twinax cable are male DB9 connectors that plug in at the host and enclosure. The shield on each end of the cable connects directly to the connector shield, providing a DC ground on both ends.


Note: Copper cables longer than 10 meters must be equalized.


Fibre Optic Cable Distances

Silicon Graphics fibre channel products support 62.5 μm optical cable and a maximum distance of 300 meters.

Cable Labels

Included in the Fibre Channel XIO board shipment is a label kit for identifying fibre channel cable connectors. Use these labels to identify which controller on which option board is supporting a particular fibre channel storage enclosure, fibre rack, or loop.