Server generally, the system switch machine should strictly follow the following steps:
Turn on the total power supply.
Turn on the computer cabinet power
Power on external devices (such as disk arrays, tape libraries, etc.)
When the external device self-test is complete, power on the host is finally turned on.
2. Shutdown sequence
Operating system shutdown (Shutdown-h-y 0)
Power off the host.
Power off the peripherals. (such as disk array, tape library, etc.)
Turn off other equipment power and cabinet power;
Finally turn off the total power supply.
3. Cable Connection Considerations
When making a cable connection (plug), the most important point is that the device through which the cable is connected (or will be connected) should not be powered, that is, the device should be turned off before the cable Connection (plug) operation. Otherwise, if the cable is electrically connected, it can cause unexpected damage to the device.
4. Hardware fault Diagnosis
Here is a brief overview of common fault handling.
Cable Connection
Note that the connection between the computer and the peripherals is good, do not unplug the cable without reason; If a computer does not recognize a device, it may be a contact problem with the cable.
Hardware Status Indicator
If you find the system is not working properly, you can observe the hardware status led.
After the boot system will automatically complete self-test, diagnostics and boot boot code. The detection sequence is roughly: cache, CPU, bus, memory, I/O devices. When the related hardware is detected, the corresponding display light is lit.
Hard drives, floppy disks, tape drives and optical drive self-test, can be seen from the front panel lights on the corresponding light, indicating that the system has recognized the above equipment. Conversely, if the self-test light for a drive is not lit, it may be a problem with the device.
In addition, the SCSI interface card behind the host and the self-test LEDs on the network interface card are lit to normal. Otherwise, there may be a problem with the interface card. If you find this problem.
Error code
After each boot, the system will carry out hardware self-test and initialization, if the system hardware failure, generally can not start normally, and in the LCD screen and the console corresponding display error code and error messages.
If there is an error on the screen and a FLT on the LCD display, indicating that there is a failure, should be based on the above tips to determine the point of failure.
Most of the hardware errors can be exposed in the self-test, in the LCD display and the lower left corner of the console have four-bit error code: FLT xxxx.
Analysis of the four-bit code can further detect the failure.
