INTERNET DOMAINS

We have used Linux since 2000 when it was first available. Previously we used BSD Unix. Open source has the advantage that when the developer becomes unavailable then the code can be maintained by new developers. Open source has allowed developers from around the world to flourish while reducing costs. The main focus of the …

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OPEN SOURCE DEFINITION

One of the founders of the open source movement, Bruce Perens, who had previously drafted the Debian Free Software Guidelines (which would be adapted to become the OSD), puts the date at February, 9, 1998, when he published an announcement of the OSD. Debian is one of the early distributions of Linux. Free and open source software meant anyone …

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EIA-310-D STANDARD RACKS

The EIA 310-D standard rack is 19 inches wide for servers, This has been in use for many decades as data centers galore can then use commodity machines for various purposes. EIA racks units are 1¾ inches. So generally servers are 1U, 2U or 4U however some blade boxes may be as large as 10U. …

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SSD RELIABILITY

Solid State NAND based flash drives surfaced in 1991 when Sandisk introduced a 20MB product for $1000. Since that early drive, prices have fallen considerably. NAND based SSD products have come in a rage of form factors however the focus of this study will be with SATA drives. Eventually we may add second section for …

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FIX HARD DISK CLICKING

First off you should own lots of disks so that redundant copies of important data does not get lost. This guide is not an easy solution and a disk may be wiped when repaired. The clicking sound is generally caused by a faulty logic board. Replacing the logic board requires the exact make and model disk …

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FAILED HARD DISKS

Every data center has had it fair share of disk failures. So far we have experienced very few disk failures. Clicking sounds, for example, indicate that the head is seeking back and forth and the disk does not present to the BIOS etc. We experienced 2 failures with 500GB disks arising from changes in soldering. The …

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OUR EIDE DISKS

ATA disks, later called EIDE, were introduced in 1985 with a lower cost controller board. The control logic was moved to logic board on the disk assembly which free manufacturers to design new products more easily. The 40-pin cable was eventually replaced with an 8-conductor wire to allow for higher speeds. EIDE hard disks are …

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BAD SECTORS

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In the early days of hard disks, manufacturers placed bad sector tables on the labels of the disks. This was done so that manual marking of bad sectors could be done. The image shows an old MFM  hard disk with its defect table. This was typical of early hard disks. MS-DOS formats disks completely and …

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HARD DISK SURVIVAL

Almost everyone has had disk errors at one time or another. There are the file system errors but this page is concerned with mechanical failures of hard disks. We purchase hard disks frequently primarily to take advantage of capacity increases. The photo is the ST-506 5MB hard disk ($1,500) that was the less expensive of …

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GNU PROJECT

The GNU project was established in 1983 by Richard Stallman when he posted a message in Usenet. Its aim is to give computer users freedom and control in their use of their computers and computing devices, by collaboratively developing and providing software that is based on the following freedom rights: users are free to run the …

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