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Hot-Swapping IDE Drives?
Patman asks: "I've recently taken a new job where I'll need to be making drive images and such for quite a few IDE drives - say a few a day. I need the ability to 'hot-swap' IDE drives into a running Linux or Windows system. The systems that I'm using are fairly standard IBM desktop PCs, I've found references on Google to IDE->USB converter cables and IDE->USB converter boxes.
Does anyone have experience with those? Some come with drivers for Windows - has anyone used them under Linux? Does the mass storage USB code deal with them accurately? Barring that, does anyone have any other ideas? External hot-swapping would be ideal, although an internal solution would be doable, too."
I can't seem to find any fix, the driver software doesn't permit caching to be disabled in the advanced properties box, so it's rendered an otherwise fine 120 GB Western Digital drive as an expensive paper weight, at least as far as Windows is concerned.
From what I've been able to read, it appears that Linux knows better, and respects the 128k per packet limit, and doesn't have this issue, but I've not confirmed that yet.
It's a bitch to be doing a backup (using copy) of 45 Gb of photos, and lose a few along the way.
--Mike--
Grab a IEEE1394 IDE bridge, preferably bus powered. Linux should support these devices and they are easily, externally hot-swappable. I've had success with the SuperDriveDock from Wiebetech, although there are certainly cheaper models out there.
Hot-swapping an IDE HDD on my winXP box. Not sure what I was thinking, but I burned two HDDs and a motherboard doing it...
Oh, you mean WITHOUT destroying your system? Sorry, can't help you...
L
Wouldn't FireWire be better, considering FireWire-IDE bridge enclosures are readily available and actual throughput is much faster usig the Oxford 911/922 chipsets?
Blue skies, Barthy Burgers, girls...
Okay, I use a USB drive enclosure on Linux to do my backups, and it works pretty well.
However, it took me a very long time to learn to set the 'sync' option in the mount options. USB writes much more slowly than a normal harddrive, and if sync isn't set, it is possible for the system to buffer all writes to the drive up to the point where it consumes most system memory, and the machine becomes unresponsive.
Perhaps this is fixed in 2.6; but it doesn't really matter. You are doing backups, the backup isn't done until it's all on the disk, so setting the sync option just means that your writes "seem" to take longer, and your unmount at the end seems faster. Without sync, you pay for the buffering in the unmount, which will hang while it finishes syncing the disk.
-- Crutcher --
#include <disclaimer.h>
Yeah, been using two of these 3ware cages (plus their Raid5 IDE controller) to RAID5 8 drives for months, quite a joy. You can pull out one of the drives mid-anything and watch the hot spare kick into gear.
Their online tech support is quite good too, replies within 1 working day.
Can't you stop being a cheapskate and just buy a proper hotswap enclosure?
If you can't afford that then a Firewire enclosure will be good enough for what you're trying to do. Make SURE to stop the device before unplugging it! You can buy Firewire dongle devices like the DriveDock from WiebeTECH as you'll be wanting to unplug and plug lots of drives.
Go to 3Ware
It is really well supported in Linux (and been since a while) as well as in M$. It supports Hot-Swap and Hot-Spare...
Francis Provencher
"What if the bird will
Windows XP has an option for not caching Firewire writes. You can then just remove and reconnect the drive without any other adjustment and without data loss. If you have audio on, there is a tone when the drive is connected or disconnected.
2000 Professional and Server are the exact same thing
Forget drivers... the only difference is the productID when installing. The install CD contains the exact same files, and the service packs are exactly the same. Hell, they even use the same kernel binary.
It just artificially limits the number of CPUs and RAM.
So whatever is true for Professional will automatically be true for Server, and vice versa.
You should really be looking at something centralized like Retrospect (which isn't too expensive, unlimited clients). Or DVD-Rs.
And tapes can work great. You just have to figure out how to justify spending over $6000 to get an AIT-3 drive or something.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
But since this method doesn't force a bios scan, it hangs if the drives have different disc/cyl/head geometries, or different partition sizes.
The Web is like Usenet, but
the elephants are untrained.
Vipower makes a ton of products that look like they might suit your needs. Keeping the drives in the little "mobile rack" caddies is probably a good idea, since exposed circuit boards left laying around the office are just asking for Ms. Mohair Sweater to come touch them.
As has been pointed out, it's possible to stop IDE devices and disconnect them with the machine on, but this is like playing Russian Roulette. In a spec designed for hot swap, the ground and power connections mate first and disconnect last, to keep the signal connections from carrying any initial current surges. IDE/ATA has no such provision, and hot matings/removals might damage your drive and/or controller. (The same goes for PS/2 keyboards and mice! Just because it works the first 100 times doesn't mean you won't fry your motherboard the 101st time, when the connector goes in a bit sideways.)
Serial ATA on the other hand, does allow for hot swapping, and USB is obviously designed for it. If you can get away with using exclusively SATA drives, check out some of the Supermicro drive racks. If you're building your own RAID system, these things are the way to go. I got a Supermicro server case second-hand and have been extremely impressed with the thoughtfulness of the design. Well-engineered products are rare and special, especially in this cheaper-sooner-cheaper industry.
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