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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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RODIME RO352

The Rodime RO352 is he first hard disk available in the 3½” format. This disk cost $1,895 when new in 1983. 11MB ST506 interface 306 cylinders 4 heads 17 sectors 306 landing zone type 02 3600rpm The Rodime RO0352  is a MFM hard disk in the 3½” format . There are two models in the series, RO351 and …

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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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NETWORK ATTACHED STORAGE

Linux is more popular choice for network attached storage (NAS). The operating system is free and there are now distributions that are turnkey for rapid deployment. Consumer NAS units range from 2 to 4 disks. Corporate servers now use 60 disk chassis that have 4 rows stacked inside a standard 4U chassis, FREENAS FreeNAS is based …

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HARD DISK LIMITS

One of the most frustrating problems a lot of DIY enthusiasts came up against was BIOS problems that prevented the use of larger capacity disks. In the early days, DOS version 1 which came on a floppy with our original PC could not even use directories. All saved files had to be saved in the …

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TAPE BACKUP

Back at the dawn of computers in the early 1950s there has been a need for a backup. IBM came up with their 7 track 1/2 inch in 1952. The image shows the IBM 705 tape system with several drives along the wall. Over time the mainframe system used a range of tape products. The …

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