Dell PowerEdge 4400 User Manual
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Maintaining the System:
Dell™ PowerEdge™ 4400 Systems User's Guide
Overview
Proper use of preventive maintenance procedures can keep the system in top operating condition and minimize the need for costly, time-
consuming service procedures. This file contains maintenance procedures that you should perform regularly.
Data Preservation
Everyone inadvertently deletes files at one time or another. Also, hard-disk drives can fail after extended use, so it is not a question of whether you
will eventually lose data, but when. To avoid such loss of data, you should regularly make backup copies of all hard-disk drive files. Frequent,
regular backups are a must for anyone using a hard-disk drive.
Scheduling Backups
The frequency with which backups should be made depends on the amount of storage space on a hard-disk drive and the volatility of the data
contained on the drive. Heavily used systems require more frequent backups than systems in which files are seldom changed.
Dell recommends that you back up the hard-disk drive at least once a week, with a daily backup of those files known to have been changed.
Following these guidelines ensures the loss of no more than a day's work in the event of a hard-disk drive failure or if you inadvertently delete one
or more important files.
As further insurance against data losses, you should keep duplicate copies of the weekly and monthly backups at an off-site location. Doing this
ensures that you lose no more than a week's work, even if one of the on-site backups becomes corrupted.
Backup Devices
Tape drives are fast, convenient, and reliable devices that can back up data at rates of up to 1.5 megabytes per second (MB/sec) (sustained,
without data compression) and can often run unattended. Dell offers tape drives with storage capacities in the range of 20 to 70 gigabytes (GB)
per tape cartridge and recommends these drives and their associated backup software for use as system backup devices.
As a last resort, you can back up a hard-disk drive's contents on diskettes, a method that is both time-consuming and prone to human error. Also,
backing up a full 4-GB hard-disk drive requires approximately 277 diskettes (when using 1.44-MB diskettes), 334 diskettes (when using 1.2-MB
diskettes), or 139 diskettes (when using 2.88-MB diskettes). Therefore, if it is absolutely necessary to use diskettes as backup devices, any
unwanted hard-disk drive files should be deleted before a backup procedure is started.
Recovering Data
Some hard-disk drive failures are recoverable. In these cases you may be able to recover all lost data if the proper utility software is available.
Even losses such as accidentally deleted files or accidental reformatting of a hard-disk drive can be reversed with these utilities.
If the system is running the MS-DOS
®
operating system, many apparent data loss problems are due to corruption or erasure of the hard-disk
drive's master boot record (MBR), MS-DOS boot sector, or file allocation table (FAT); that is, accidental deletion of files or accidental reformatting
of the hard-disk drive alters the MS-DOS boot sector, the FAT, and the root directory.
However, such accidents do not actually erase the contents of the hard-disk drive files until new data is written to the sectors containing these files.
With software such as the Norton Utilities, Mace Utilities, or PC-Tools Deluxe, the data stored in these areas can often be restored, meaning that
you can recover most, if not all, of the data.
Unlike using the format command on a hard-disk drive, using format on a diskette completely erases all the data on the diskette unless you use the
diskette format program included in the Mace Utilities.
For a complete description of data recovery procedures and the software needed to perform them, see The Paul Mace Guide to Data Recovery,
published by Brady.
Cleaning System Components
An exhaust fan in the power supply cools the power supply and system by drawing air in through various openings in the system and blowing it out
the back. However, the fan also draws dust and other particles into the system, causing contaminant buildup, which results in an increase in the
system's internal temperature and interferes with the operation of various system components.