Apple xserve early 2008 User Manual

							Xserve (Late 2006) Troubleshooting — General Information 131
Selecting an Alternative Startup Method from the Front Panel
You can use the Xserve’s front panel controls to choose from optional startup methods that 
might be helpful in special circumstances.
To choose an alternative startup method from the front panel:With the power off, hold in the system identifier button while you press the on/standby 
1.  
button.
Continue to hold in the system identifier button until the top row of blue lights blinks 
2.  
sequencially.
Release the system identifier button, and then press it again repeatedly to turn on the light 
3. 
that corresponds to your chosen startup method:  
Start up from
disc in optical driv eStar
t up from
NetBoot ser ver Star
t up from first
av ailable system on an
internal drive module Sk
ip current star tup disk
and star t up from an y
other av ailable system
Star t up in
target disk mode Reset NVRAM and star
t up
from first bootable drive module Not used
Start up in diagnostic
mode from a NetBoot ser ver
When you have made your choice, hold in the system identifier button until all lights on the 
4.  
top row are on, and then release.
The Xserve starts up using the chosen method.
Ports
The Xserve includes the following ports on the back panel: two gigabit Ethernet ports, two 
FireWire 800 ports, two USB 2.0 ports, a built in mini-DVI display port, and a serial port that 
supports RS-232 or RS-422 connection. There is also one FireWire 400 port on the front of the 
Xserve.
System administrators or service providers can connect a laptop computer or terminal to the 
serial port and then use command-line tools to change settings on the Xserve. The connection 
requires a serial cable with these specifications: DB9 connector
• 
8-bit
• 
no parity
• 
1 stop bit
• 
9600 kbps
• 
Note: For a diagram of all front- and rear-panel port locations, see “External Views” in the Views 
chapter. 
						

							Xserve (Late 2006) Troubleshooting — General Information 13 2
Resetting the Logic Board 
System Management Controller (SMC) Reset
The System Management Controller (SMC) is a chip on the logic board that controls all power 
functions for the Xserve. If the Xserve is experiencing any power issue, resetting the SMC may 
resolve it. The SMC controls several functions, including: Telling the Xserve when to turn on, turn off, sleep, wake, idle, and so forth 
• 
Handling system resets from various commands 
• 
Controlling the fans 
• 
It is also recommended that the SMC be reset on any new logic board after it is installed as part 
of a repair. 
Note that resetting the SMC does not reset the PRAM. Resetting the SMC will not resolve issues in 
which the Xserve is unresponsive—in these situations, restarting the Xserve will generally suffice. 
If the Xserve isn’t responding, perform these steps one at a time, in the following order, until the 
issue has been resolved: 
Force Quit (Option-Command-Escape) 
1.  
Restart (Control-Command-Power) 
2.  
Force Shut Down (press the power button for 10 seconds) 
3. 
Resetting the SMC can resolve some Xserve issues such as not starting up, not displaying video, 
sleep issues, fan noise issues, and so forth. If the Xserve still exhibits these types of issues after 
you’ve restarted the Xserve, try resetting the SMC. There are two ways to reset the SMC on the 
Xserve.
To reset the SMC in the Xserve (Late 2006): 
Shut Down the Xserve, either locally or using remote commands (or if the Xserve is not 
1.  
responding, hold the power button until it turns off ).
Unplug the AC power cord. 
2.  
Wait at least 15 seconds. 
3. 
Plug the power cord back in, making sure the power button is not being pressed at the time. 
4.  
Press the power button to start up the Xserve. 
5. 
Real Time Clock (RTC) Reset 
The Real Time Clock (RTC) is a chip on the logic board that controls the date and time functions 
of the Xserve. If the Xserve is experiencing an issue booting, resetting the RTC may resolve it. 
Follow these steps to reset the RTC: 
Shut Down the Xserve, either locally or using remote commands (or if the Xserve is not 
1.  
responding, hold the power button until it turns off ). 
						

							Xserve (Late 2006) Troubleshooting — General Information 13 3
Unplug the AC power cord. 
2.  
Remove the battery for at least 20 seconds.
3. 
Reinstall the battery and wait 5 seconds, then press the power button on the front panel to 
4.  
start up the Xserve.
You will need to re-set the system date and time to the current date and time since these 
5. 
parameters will be reset when the RTC is reset.
System Reset 
The Xserve has a system reset switch on the logic board that may be used to restart the Xserve 
while it is powered up. This switch can be used to determine if a Xserve that won’t consistently 
boot from a cold start has power supply issues. Follow these steps to reset the system: 
With the Xserve powered up, press the SYS_RST switch located on the logic board to the rear of 
the FB-DIMM slots.
If the Xserve boots after you press the SYS_RST switch, try shutting the Xserve off and restarting 
by pressing the front panel power button. If the Xserve restarts when you press the SYS_RST 
switch but not from a cold start, the power supply may need to be replaced. 
Power-On Self Test (POST) Error Indications 
A power-on self test in the Xserve’s ROM automatically runs whenever the Xserve is started 
up after being fully shut down (the test does not run if the Xserve is only restarted). If the test 
detects a problem, the status LED located above the power button on the front of the Xserve will 
flash in the following ways*:
One short flash followed by a longer off period
If the system does not have any valid memory to boot from due to (1) no FB-DIMMs detected, (2) 
memory initialization failure or (3) a quick memory test failure, then the front panel status LED 
will blink once repeatedly.
Three short flashes followed by a longer off period
If the quick memory test passes but the more exhaustive memory test later in the boot sequence 
fails, then the front panel status LED will blink three times repeatedly, and the FB-DIMM LED will 
illuminate red for the respective FB-DIMM.
Troubleshooting: Try reseating the memory FB-DIMMs. Check memory installation instructions for proper 
• 
installation order. Swap affected FB-DIMM with known good FB-DIMM.
*Note: The status LED lights up when the power button is depressed at startup. Do not count 
this light as one of the diagnostic flashes.  
						

							Xserve (Late 2006) Troubleshooting — General Information 134
Diagnostic LEDs
The logic board includes three sets of LEDs to help service providers troubleshoot the Xserve:System status LEDs (1 in the illustration below)
• 
CPU status LEDs (2 in the illustration below)
• 
EFI POST LEDs (3 in the illustration below)
• 
The LEDs are located toward the rear of the logic board. You must remove the top cover of the 
Xserve for the diagnostic LEDs to function.
Refer to the charts and information on the following pages for how to interpret the LEDs. 
						

							Xserve (Late 2006) Troubleshooting — General Information 13 5
System Status LEDs
LocationNameNormal State Indicates
DS9C3 SLEEPON (Red) System is in sleep mode.
DS9C4 5VSTBYON Power supply is providing trickle power.
DS9C5 EFI_GDNormally OFF; only 
flashes during boot 
cycle Normal sequence indicates control has passed 
from EFI operations to the OS. If light stays on 
after boot cycle, EFI is crashing.
DS9C6 VR_PWRON System is powered on.
DS9C3: SLEEP
Important: The red DS9C3 LED warns that the Xserve is in sleep mode. When this LED is ON, do 
not remove or replace PCI expansion cards or FB-DIMMs, because the Xserve is still powered on.
DS9C4: 5VSTBY
If the DS9C4 LED is OFF, do the following: Check that the AC cord is connected to a working AC wall outlet. 
• 
Reseat the AC plug.
• 
Reseat the power supply. 
• 
Replace the power supply.
• 
DS9C5: EFI_GD
If the DS9C4 LED is OFF, do the following:
Reset PRAM.
• 
Boot off an install disc. 
• 
If the system does not boot from the install disc, replace the logic board.
• 
Replace the FB-DIMMs.
• 
Reseat CPU A.
• 
Reseat CPU B.
• 
Replace CPU A.
• 
Replace CPU B.
• 
DS9C6:  VR_PWR
If the DS9C6 LED is OFF, do the following: Check for any signs of an obvious electrical short, e.g. metal screws or PCI card slot cover 
• 
loose inside Xserve touching the logic board.
Reseat the power supply.
• 
Replace the power supply.
•  
						

							Xserve (Late 2006) Troubleshooting — General Information 13 6
CPU Status LEDs
LocationName Normal StateIndicates
DS9C1 CPUB_OVERTMP OFFCPU B is operating at the right temperature.
DS9C2 CPUA_OVERTMP OFFCPU A is operating at the right temperature.
DS9C7 CPUB_HLTH OFFCPU B is operating correctly.
DS9C8 CPUA_HLTH OFFCPU A is operating correctly.
Note: Under normal operating conditions, the CPU status LEDs are all OFF; however, there may be 
exceptions. Refer to KnowledgeBase article ????
DS9C1: CPUB_OVERTMP and DS9C2: CPUA_OVERTMP
Note: These two LEDs can operate in two different modes; they will either flash or stay on. If 
either LED is flashing, it may indicate an initial processor over-temperature condition. If either 
LED is solidly on, it may indicate a chronic processor over-temperature condition. Initial processor 
over-temperature can cause symptoms such as sluggish Xserve performance. Chronic processor 
over-temperature can cause the Xserve to hang completely.
If DS9C1 or DS9C2 LED is ON, do the following: Verify proper heatsink installation.
• 
Verify all thermal sensors are properly connected.
• 
Verify the fan array is operating properly.
• 
Verify the airflow duct is properly in place and nothing is blocking its airflow.
• 
DS9C7: CPUB_HLTH and DS9C8: CPUB_HLTH
If DS9C7 or DS9C8 LED is ON, do the following:
With the Xserve booted, press the SYS_RST switch. If this turns off the LED, check for 
• 
incompatible device driver software that may have been installed for added hardware.
If the LED is still on, power down the Xserve and try resetting the SMC. Restart the Xserve.
• 
Reset the power supply by unplugging the AC cord for 20 seconds.
• 
Unplug the AC cord and remove any added FB-DIMMs and PCI Express cards. If this causes 
• 
the LED to go off, repopulate the FB-DIMMs and/or PCI Express cards to find the combination 
that caused the LED to come on. Overheated memory could be a possible cause for this LED 
to come on. Check fan array operation.
Unplug the AC cord and remove the battery for 10 seconds. Reinstall the battery, wait 5 
• 
seconds, and restart the Xserve.
Try swapping CPU A and CPU B locations. If the LED follows the CPU, replace that CPU.
• 
Try replacing the logic board.
• 
EFI POST LEDs
The four EFI POST LEDs, DS1–DS4, are tri-state colored LEDs that may be green, red, or amber. 
When the Xserve (Late 2006) is powered on, the four LEDs light up and display different patterns 
of colors. If the system hangs, record the color for each LED and contact AppleCare technical 
support to report the pattern. 
						

							Xserve (Late 2006) Troubleshooting — General Information 13 7
Memory Diagnostic LEDs
The Xserve (Late 2006) logic board includes diagnostic LEDs for each FB-DIMM. Each of the LEDs 
will light if it detects an issue with the corresponding installed FB-DIMM. These LEDs will also 
flash briefly when the computer is started up or shut down and when it goes in and out of sleep 
mode. This is normal behavior.
Troubleshooting:Shutdown and restart the computer. 
• 
Try reseating the FB-DIMMs. 
• 
Check memory installation instructions for proper installation order. 
• 
Swap affected FB-DIMM with known good FB-DIMM.
• 
Try moving FB-DIMM to another slot (within the same bank of two) to see if the failure LED 
• 
follows the FB-DIMM.  If so, replace FB-DIMM with known good FB-DIMM. 
						

							Xserve (Late 2006) Troubleshooting — General Information 13 8
Power Supply Verification
To power on, the Xserve’s logic board requires “trickle” power. If the system fails to power on, 
first reset the SMC as described in this chapter. If the Xserve still doesn’t power on, follow the 
procedure outlined below to determine whether the issue is related to the power supply.
Verify trickle power
Diagnostic LED DS9C4 (5VSTBY ) indicates the presence of trickle power required by the logic 
board to begin the startup process. 
LED DS9C4 should be ON when the power supply is plugged into a good AC outlet, indicating 
that trickle voltage is present.
Verify Power Supply Is Providing Power
Diagnostic LED DS9C6 ( VR_PWR) indicates that the main power is OK and within regulation.
Plug in AC power cord, and press the power-on button on the front panel.
LED DSC9C6 should be ON when the Xserve starts up, indicating that the main power is OK and 
within regulation.
If you cannot verify these LEDs are on, try replacing the power supply with a known-good one.  
If you are working with an Xserve with two power supplies, try removing one and test one at a 
time to determine which one may have the issue.  Also try the same known-good power supply 
in each power supply bay, to see if the issue is related to a single bay or not.
If you try a known-good power supply in both bays and you are still having power issues, try 
replacing the power distribution board.
Internal Sensor Locations
Xserve (Late 2006) includes many built-in sensors that report on hard drives, internal 
temperature, fan status/failure, and power status/failure. These sensors allow you to monitor the 
Xserve’s operation.
For more detailed information, see the “Appendix” at the end of this manual. 
						

							Xserve (Late 2006) Troubleshooting — General Information 13 9
Front Panel Status Lights 
The Xserve’s status lights are shown in the figure below.
Drive module
ac tivit y ligh t
Driv
e module
status ligh t Optical driv
e
System identifier
button/ligh t
Enclosure lock
and status ligh t
FireWire 400
po rt
On/standby button
and ligh t
Drive Module
bays (3)
Ether
net link ligh t
(P or t 1) Ether
net link ligh t
(P or t 2)
System ac tivity
lights
Note: The front bezel of the Xserve (Early 2008) model is identical to the Xserve (Late 2006) image 
above except the FireWire 400 port is replaced by a USB port, as shown below:
On/standby button and light
On/standby button and light. Press to turn on the Xserve. Press for 10 seconds to force the Xserve 
to shut down if all other shutdown methods fail.
Enclosure lock and lock status light
The lock secures the Xserve cover and drive modules. It can be locked and unlocked with the 
enclosure key supplied with the Xserve. An option in the Security pane of System Preferences 
lets you inactivate a connected keyboard and mouse when the enclosure lock is engaged. This 
option is turned off by default.  When the enclosure is locked (the light is on), the Xserve might 
not recognize peripheral devices such as a keyboard, mouse, or storage device. Unlock the lock to 
use those devices. 
						

							Xserve (Late 2006) Troubleshooting — General Information 140
System identifier button and light
The system identifier light flashes if a problem is detected. You can also turn it on manually 
by pressing the button or turn it on remotely using Server Monitor. This indicator is useful for 
locating a particular unit in a rack with more than one Xserve. A second system identifier button 
and light are on the rear panel.
Ethernet link lights
Two lights indicate whether the Xserve is connected to an Ethernet network. Each light reflects 
one of the two built-in Ethernet ports: the bottom light port 1 and the top light port 2.
System activity lights
Four groups of four lights indicate system activity. The front panel system activity LEDs will flash 
blue intermittently to represent an estimate of processor activity and load. Each row is divided 
in half so four lights represent each of the four processor cores.  You also use these lights to 
select an alternative method for starting the Xserve using the front panel startup options; see 
“Choosing an Alternative Startup Method from the Front Panel” in this chapter.
System ac
tivity lights
Drive module (upper LED)
Green - Powered and running
• 
Yellow - Warning condition; replace drive
• 
Red - Problem or failure; replace drive
• 
Driv e module ac tivity light (blue)
Driv
e module status light (green)
Drive module (lower LED)
No light - Drive can be removed
• 
Blinking blue - Disk activity; do not remove drive
•