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hard drives

Maximum Number of Disks In RAID 5

Is there a limit to how many drives you can have in one RAID-5? What is the maximum number of physical drives recommended in a RAID-5 set?
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Linux Disable USB Devices (Disable loading of USB Storage Driver)

In our research lab I'd like to disable all USB devices connected to our HP Red Hat Linux based workstations. I'd like to disable USB flash or hard drives, which users can use with physical access to a system to quickly copy sensitive data from it. How do I disable USB device support under RHEL 5.x workstation operating systems?
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FreeBSD: Get / Read Hard Disk Temperature Using smartd Tools

How do I read my hard disk temperature using smartool under FreeBSD operating system?
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Howto rebuilding a RAID array after a disk fails

Q. I have two disk-mirrored array, suppose if one of my disk in mirrored RAID array fails, then I will replace that disk with new one (I have hot swapping SCSI drives). Now question is how I rebuild a RAID array after a disk fails.

A. A redundant array of inexpensive disks, (redundant array of independent disks) is a system, which uses multiple hard drives to share or replicate data among the drives. You can use both IDE and SCSI disk for mirroring.

If you are not using hot swapping drives then you need to shutdown server. Once hard disk has been replaced to system, you need to use used raidhotadd to add disks from RAID-1, -4 and -5 arrays, while they are active.

Assuming that new SCSI disk is /dev/sdb, type the following command:# raidhotadd /dev/mdX /dev/sdbReplace /dev/mdX with actual raid device name (e.g. /dev/md0). While array is under construction, you can see progress and other information by typing following command:# cat /proc/mdstat

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