[ILUG] Hot swap drive?
John P. Looney
valen at tuatha.org
Thu Jul 22 10:57:33 IST 2004
On Thu, Jul 22, 2004 at 10:23:45AM +0100, Niall O Broin mentioned:
> Oh - you certainly CAN'T unplug a mounted drive, no matter what the hardware
> arrangements, without risking massive FS corruption. Always umount first. Kate
> tells a nice story about an SA in a certain large company, anxious to
> demonstrate his shiny Sun RAID system with hot plug drives, unplugged some
> drives without informing the OS of his intentions. This did nothing but bad to
> the database which was using the disks at the time.
I think the conversation was more like;
"Hi, you know that new E450 we bought, with 20 SCSI disks in it ?"
"They are hot-swap disks, yes ?"
"Yes, once you've marked them as offline in the OS, or the RAID
controller has worked out they are faulty, and switched them to offline".
"Ah. That's why Oracle crashed"
"What happened ?"
"Well, the boss wanted to see RAID in action. So, I pulled out some of
the disks to test the system. After I pulled out the 15th disk, users
started reporting problems with Oracle"
"I'll order you fifteen replacement disks, and an engineer to install
them and restore Oracle from backups for you. We'll have to charge for
the disks, I'm afraid, as a 10k spinning disk getting yanked is likely
"Oh. We don't back stuff up, as it's all RAID...."
> A better option might be an external USB-2 (USB is rather slow for a big
> drive) or Firewire drive. If your box doesn't have USB-2 or Firewire, add-in
> cards are relatively cheap.
€50 for a USB2 hard drive cradle from Komplett. Warning: they have a PS/2
shaped PSU connector. Plugging one of these into your keyboard socket will
result in a fryed motherboard.
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