Back to Contents Page

Basic Troubleshooting

Dell™ PowerVault™ 220S and 221S Systems Service Manual

	Overview		Troubleshooting the System
	Safety First—For You and Your System		Troubleshooting a Cooling Module
	Indicators Overview		Troubleshooting a Power Supply
	Troubleshooting SCSI Hard Drives		Troubleshooting Common Faults and Errors

Overview

This section provides information to help you troubleshoot problems with your storage system and its components. It includes a summary of common system faults along with corrective actions. This section focuses primarily on hardware-based troubleshooting. For more information on troubleshooting using storage system configuration and management software, see your array management software documentation. See "Components and Indicators" for locations of front- and back-panel LED indicators. Dell recommends that you perform the following procedures in the order presented.

NOTE: When you see the question "Is the problem resolved?" in a troubleshooting procedure, perform the operation that caused the problem.

Safety First—For You and Your System

While working on the system, do not attempt to service the system except as explained in this guide and elsewhere in your system documentation. Always follow the instructions closely. Review all of the procedures in the safety instructions in your System Information document.

Indicators Overview

The LED indicators on your storage system provide valuable information when troubleshooting the system. Table 9 lists the most common system and component faults and tells you where to look in this section to find more information on correcting the problem. For locations and descriptions of LED indicators, see "Components and Indicators."

Table 9. Common System and Component Faults

Troubleshooting SCSI Hard Drives

Hard-drive problems can be caused by a number of conditions, including problems with the drive itself, other electronics in the system, or an interface cable.

You can resolve many hard-drive problems by validating your SCSI cable connections as described in your Installation and Troubleshooting Guide.

NOTE: Not all SCSI cables are interchangeable. For your storage system to function properly, it is recommended that you use the cables shipped with the system. If you are using other SCSI cables, they must be approved for U160 use.

In the event of a drive failure, the following SCSI hard-drive indicator LEDs are illuminated (see Figure 2 for LED indicator locations):

• Predicted failure — The status indicator flashes green, then amber, then off, repeating this sequence every two seconds if a drive is showing signs of imminent failure.
  
  
• Drive failure — The status indicator flashes amber four times per second if a drive fails.

For a list of all SCSI hard-drive LED flash patterns, including the ones described previously, see Table 3.

To troubleshoot your SCSI hard drives, complete the following steps:

1. Is the storage system turned off?

Yes. Turn on the storage system using the on/off switch on the back of the power supply (see Figure 8 for switch location).

No. Go to step 2.

2. Is the SCSI cable(s) damaged or not attached securely to the SCSI connectors on the EMM(s) and the host controller?

No. Go to step 3.

Yes. Secure the cable(s) or check connector pins for damage. 

3. Does the bus configuration switch mode match your cabling configuration? For example, if you are operating in split-bus mode, is the cabling between the host(s) and the storage system appropriate for this mode? (For more information on cabling configurations, see your Installation and Troubleshooting Guide.)

Yes. Go to step 4.

No. Change either the bus configuration switch mode or cabling between the host and storage system. Then reboot the storage system and the host.

4. Are the status LED indicators for all the hard drives illuminated?

Yes. End troubleshooting.

No. Go to step 5.

5. If a hard drive's status indicator is off, reseat the hard drive by removing it from its drive bay and reinstalling it (see "Removing and Installing Hard Drives"). Is the problem resolved?

Yes. End troubleshooting.

No. Install a new hard drive. Because it is possible to move failed drives between slots, do not swap hard drives.

Troubleshooting the System

When the storage system is turned on, the system performs a POST, which checks all the components. During POST, all of the indicators for each SCSI hard drive blink briefly, and all of the system indicators are illuminated. When the POST is complete, the indicators are illuminated based on the descriptions in Table 2.

If one of these events has occurred, perform the following steps to troubleshoot:

• Amber shelf fault LED is illuminated
  
  
• Audible alarm sounds (when enabled)
  
  
• Drive(s) not seen during the host boot

1. Is the green AC status LED indicator on the power supply(s) illuminated? (See Figure 8 for location.)

No. See "Troubleshooting a Power Supply."

Yes. Go to step 2.

2. Is the amber over-temperature LED on the front of the system illuminated? (See Figure 2 for location.)

No. Go to step 3.

Yes. One or more temperature sensors are in the warning range. Check environmental conditions (high ambient temperatures, ventilation blockage, etc.) and cooling modules for failures. Replace failed cooling modules (see "Replacing a Cooling Module"). For more information, see "Troubleshooting a Cooling Module."

3. Is the amber fault indicator on the back of the power supply illuminated? (See Figure 8 for location.)

No. Go to step 4.

Yes. A power supply has failed. Replace the failed power supply (see "Replacing the Power Supply"). For more information, see "Troubleshooting a Power Supply."

4. Is the amber fault indicator for either cooling module blower illuminated? (See Figure 8 for location.)

No. Go to step 5.

Yes. One of the cooling module blowers has failed. Replace the failed module (see "Replacing a Cooling Module"). For more information, see "Troubleshooting a Cooling Module."

5. Is the amber fault indicator on an EMM illuminated? (See Figure 5 for location.)

No. Go to step 6.

Yes. An EMM has failed. Replace the EMM (see "Removing and Installing an EMM or SCSI Terminator Card").

6. Is the power indicator on the split-bus module illuminated? (See Figure 5 for location.)

Yes. Go to step 7.

No. The split-bus module has failed. Replace the split-bus module (see "Removing and Installing a Split-Bus Module").

7. Are the pins on the SCSI cable damaged or is the cable between the host and the storage system disconnected?

No. Go to step 8.

Yes. Secure or replace the cable.

8. Replace the SCSI backplane board. See "Replacing the SCSI Backplane."

Troubleshooting a Cooling Module

The LED fault indicators for the cooling modules are located in the upper-right corner of each power supply (see Figure 8). If one of the two blower fault indicators is illuminated or your array management software issues a blower-related error message, replace the cooling module (see "Replacing a Cooling Module").

NOTICE: The maximum amount of time that power supply and cooling modules may be removed from the system while it is operating is 5 minutes. If power supply and cooling modules are not replaced within 5 minutes, the system begins to overheat. When the system reaches a critical temperature, it shuts down to prevent damage to the system.

Troubleshooting a Power Supply

The three power-supply LEDs on the back of the power supply (see Figure 8) indicate the status of the power supply when it is connected to the backplane (see Table 7 for a description of each indicator and its function).

If all three power-supply indicators are off or if the power-supply fault LED indicator is illuminated, perform the following steps:

1. Ensure that there is power at the electrical outlet and check the power cable connection from the electrical outlet to the power supply. Is the power supply receiving power?

Yes. Go to step 3.

No. Replace the power cable.

Is the problem resolved?

Yes. End troubleshooting.

No. Go to step 3.

2. Is the on/off switch on the power supply turned on?

Yes. Go to step 2.

No. Turn on the power switch.

Is the problem resolved?

Yes. End troubleshooting.

No. Go to step 2.

3. Reseat the power supply in the power-supply bay.

Is the problem resolved?

Yes. End troubleshooting.

No. Replace the power supply (see "Replacing the Power Supply").

Troubleshooting Common Faults and Errors

The following section provides procedures for troubleshooting some of the most common faults and errors.

Shelf Fault Is On With Audible Alarm

This section provides a procedure for troubleshooting your system when either a continuous or intermittent audible alarm has sounded. For a list of critical and noncritical events indicated by your storage system's audible alarm, see Table 8.

NOTE: If the audible alarm on your storage system is disabled, you will hear no alarm sound. To enable the audible alarm, see your array manager documentation.

1. Is the amber over-temperature LED on the front of the system illuminated? (See Figure 2 for LED location.) 

No. Go to step 2.

Yes. One or more temperature sensors are in the warning range. Check environmental conditions and cooling modules for blower failures. Replace failed cooling modules (see "Replacing a Cooling Module"). 

2. Is the amber fault LED on the back of the power supply illuminated?

No. Go to step 3.

Yes. A power supply has failed. Replace the failed power supply (see "Replacing the Power Supply"). 

3. Is the amber fault LEDs for blower A and/or blower B illuminated? (See Figure 8 for LED locations.)

No. Go to step 4.

Yes. One of the blowers has failed. Replace the failed cooling module (see "Replacing a Cooling Module").

NOTICE: The maximum amount of time that power supply and cooling modules may be removed from the system while it is operating is 5 minutes. If power supply and cooling modules are not replaced within 5 minutes, the system begins to overheat. When the system reaches a critical temperature, it shuts down to prevent damage to the system.

4. Is the amber fault LED on one or both EMMs illuminated? (See Figure 5 for LED locations.)

No. Go to step 5.

Yes. An EMM has failed. Replace the EMM (see "Removing and Installing EMMs and the SCSI Terminator Card").

5. Is the split-bus module installed and properly seated? (See Figure 5 for LED locations.)

No. Reseat the split-bus module (see "Removing and Installing the Split-Bus Module").

Yes. Go to step 6.

6. Replace the SCSI backplane board (see "Replacing the SCSI Backplane").

Storage System Is Not Seen During Host Boot

1. Is the storage system turned off?

No. Go to step 2.

Yes. Turn on the storage system using the on/off switch on the back of the power supply (see Figure 8 for switch location).

2. Is the SCSI cable(s) damaged or not attached securely to the SCSI connectors on the EMM(s) and the host controller?

No. Go to step 3.

Yes. Secure the cable(s) or check connector pins for damage.

3. Is the power LED on the split-bus module off? (See Figure 5 for LED locations.)

No. Go to step 4.

Yes. The split-bus module has failed. Replace the split-bus module (see "Removing and Installing the Split-Bus Module").

4. Is the amber fault LED on one or both EMMs illuminated? (See Figure 5 for LED locations.)

No. Go to step 5.

Yes. An EMM has failed. Replace the EMM (see "Removing and Installing EMMs and the SCSI Terminator Card").

5. Replace the SCSI backplane board (see "Replacing the SCSI Backplane").

Operating System Does Not See Hard Drives at Boot

If the storage system is seen during BIOS boot but not by the operating system, make sure that the correct controller device driver is installed.

Host Locks Up When Attached to Storage System

Verify that the split-bus module switch is in the correct position (see "Split-Bus Module") and that the split-bus mode matches your cabling configuration. For more information on cabling configurations, see your Installation and Troubleshooting Guide.

Amber LED Indicator on a Hard Drive Is Illuminated

A hard-drive failure has been detected. Replace the hard drive (do not swap). See "Removing and Installing Hard Drives."

Back to Contents Page