SGI Onyx 350 General Maintenance

Onyx 350 compute module with both front doors open: DVD-ROM drive, two SCSI drive sleds, the L1 display, the two power supply bays and the supply fan in the right-hand door (SGI User's Guide, Figure 1-3)

Routine care, power procedures and owner-replaceable parts of the SGI Onyx 350, from SGI's SGI Onyx 350 Visualization System User's Guide (007-4632-001) and owners' notes. The compute module is the one used in the SGI Origin 350; its memory, PCI cards, disks and cover are handled as described on SGI Origin 350 General Maintenance.

Safety

• The rack runs from 200–240 V AC; the compute modules take 120 or 240 V. Switch off before connecting or disconnecting power cords.
• Racks joined by NUMAlink or Xtown2 cables must not differ in ground potential by more than 0.25 V. Feed the InfiniteReality modules and the PDU from the same breaker box.
• Components inside a module may be hot; SGI asks for about five minutes' cooling before working inside one.
• SGI warns that only qualified service staff should replace the soldered lithium battery in the Onyx 350, which can explode if replaced wrongly.
• Wear an earthed wrist strap, and keep parts in their antistatic bags until you fit them.

Environment

Onyx 350 environmental limits (SGI User's Guide, Table A-1)

Item	Limit
Operating temperature, up to 1500 m	5 to 35 °C
Operating temperature, 1500 to 3000 m	5 to 30 °C
Non-operating temperature	−40 to 60 °C
Humidity	10% to 95%, non-condensing

Powering on and off

Before powering on, check every power cable: InfiniteReality modules to their own wall outlets; the compute, MPX, NUMAlink, USB hub and TP900 modules, the L2 controller supply and any power bay to the PDU; and the PDU to the wall. Check the USB cables from the L2 to the graphics modules and the NUMAlink module or compute modules. Set the switches of any DC-powered 4U PCI expansion module to on, and set the InfiniteReality module's rear switch last; the compute, MPX and AC-powered NUMAlink modules have no switch and their L1 controllers start when the PDU breaker is turned on.

To power on, turn on the PDU breaker and the graphics module switches, check that every L1 display reads L1 running, and then either type pwr u at the L2 prompt or press the front buttons: PCI expansion and graphics modules first, then the NUMAlink module, then the compute modules starting with the global master, usually the lowest compute module in the rack. To power off, shut IRIX down, then type pwr d at the L2 or press the buttons. The L1 controllers stay powered until the graphics module switches are turned off and the other modules are unplugged.

The procedure is the same as on the Onyx 300, where it is set out step by step.

Owner-replaceable parts

SGI's Onyx 350 guide gives owner procedures for PCI and PCI-X cards, disk drives, DIMMs, the L1 controller display and the power supplies.

Opening a module

Power the system off, remove the two screws holding the module to the front of the rack, disconnect the cables at the rear, slide the module forward to its safety latches, and remove the ten Phillips screws holding the hinged cover.

Power supplies

Removing a supply: screen cover screws, cover and fan swung aside, release and handle, supply out (SGI User's Guide, Figure 7-27)

Each compute, compute/graphics or MPX module takes one or two supplies at the front right; the left one is the primary. They can be changed with the module running only when two are fitted and both are working.

1. Power the system off.
2. Open the bezel door on the right of the front panel and remove the two screws of the screen cover.
3. Swing the screen cover, with the supply fan, aside. Take care not to snag the fan's ribbon cable.
4. Push the release button to the right, lift the green handle, and slide the supply out onto an antistatic surface.
5. Slide the new supply in with its handle open, press the handle down until it locks, close the screen cover without pinching the ribbon cable, and refit the screws.

Leave either a supply or a blanking plate in each bay, or the module's cooling will not work properly.

L1 controller display

1. Power the system off, disconnect the module's cables, wait for it to cool, take out the two rack screws and slide it out to the safety latches.
2. Remove the ten cover screws and open the hinged cover.
3. Remove the two screws of the front bezel, then the single screw of the L1 display cover, and unhook the cover.
4. Remove the two screws holding the display to its cover and unplug the display cable.
5. Fit the new display with the cable's red stripe to the left, and reassemble in reverse order.

Keyboard and mouse

The base module has four USB ports and two PS/2 ports, and USB is the default. If both are connected, IRIX numbers the USB keyboard and mouse first. To make PS/2 the primary pair, swap the numbers on the keyboard/mouse and pckb/pcms lines in /etc/ioconfig.conf; the change takes effect at the next reboot or after ioconfig -f /hw. InfinitePerformance systems always use USB as the standard connection.

Clock and NVRAM chips

jwhat explains that the Onyx 350 has two battery-backed clock chips. A Dallas DS1742W-120 holds the L1 controller's clock and configuration, including the system serial number; on the Onyx 350 it sits on the 2U interface board. A SNAPHAT battery and crystal module, clipped onto the system clock chip, keeps the system clock and the NVRAM used by the PROM; on the Onyx 350 it is on the underside of the IO9 card, which has to be removed to reach it.

• A flat SNAPHAT shows as a "preposterous date" at boot; boot to single-user mode, set the time, and replace the SNAPHAT.
• A flat Dallas shows as an L1 date and serial number that do not survive a power cycle, and can stop the machine booting.
• jwhat found that an Onyx 350 initialises a cleared Dallas chip by itself, taking the serial number from the L2 controller. He has tested drop-in replacements made in the SGI community.
• He replaced the SNAPHATs on five machines at once and found three dead and two low.

InfiniteReality graphics module

• The module has its own power cord to a wall outlet. jwhat's InfiniteReality4 module came with a Hubbell HBL2621 plug, which he replaced with an IEC 60309 16 A plug to suit Australian 240 V supplies; have any plug change checked by a qualified electrician.
• The Ktown2 and GE16-4 boards seat through compression connectors. jwhat fits such a board with its location screws first and then tightens the compression connector, using a 7/64 inch hex key under the covers; to remove one, loosen the compression connector first and the location screws after.
• Its USB connection to the L2 controller uses a cable with a DB-9 connector at the module end; jwhat had to source one.
• The 13W3 monitor cable SGI supplied is 9.1 m long.

L2 controller

The L2 needs 48 V DC. jwhat powered his from a D-Link DSA-0421S-50 adaptor wired to an HD50 plug, pins 1 to 6, using details from jan-jaap, and found that the cable from the L2 to its door-mounted display is a standard MD50 SCSI cable about 3 m (10 ft) long.

Related pages

• SGI Onyx 350
• SGI Onyx 350 Troubleshooting Guide
• SGI Onyx 350 Capacitor Replacement Guide
• SGI Onyx 350 Documentation
• SGI Origin 350 General Maintenance
• SGI Onyx 300 General Maintenance