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hotplug SATA with CentOS 5

When the SATA standard was introduced in PCs, I'd read that the electrical connections of both the data and the power connector had been designed with hotplug in mind. But just as with many hotplug-able technologies, I never actually tried it (hotplug PCI, anyone ?). Until now, that is.

Job at hand: replace the software-mirrored SATA drives in high-end Dell workstations with bigger ones. Without losing the data, of course. A perfect opportunity to test how Linux handles SATA hotplug ! Actually, adding the drive was a breeze, Linux automatically detects the drive, and I could sfdisk, and mdadm --add. Next step was hot-removing the old drives: mdadm --fail and mdadm --remove, then physically unplug the drives. I didn't expect it to be so easy, to be honest. Great technology !

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