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Build Your Own SATA Hard Drive Switch
Mikey Win writes "ExtremeTech shows us a cool hardware hack that allows multiple operating system to boot without dealing with any tedious BIOS setup changes. How? By building your own SATA hard drive switch. The result? You can expect a longer hard drive life span, power supply load reduction, and partitions protected from becoming overwritten or corrupted."
"You can expect a longer hard drive life span"
Well, assuming you build it right.
There's no -1 for "I don't get it."
Hrmph. Call me when the switch in question is tied to a massive, mad scientist-quality switch, clearly labeled in big letters with "LINUX" on one side, "WINDOWS" on the other. It should also make a satisfying mechanical switching noise whenever I pull it. And if you can make lightning crack outside my window every time, that'd be nice, too.
Demanding constant attention will only lead to attention.
Low tech and simple. The only thing I might do differently is attach the rotary knob to an unused PCI backplane thingy instead of an unused drive bay - would make it harder for inquisitive people/pets to crash things.
Long signatures suck.
Something tells me this is probably not a good idea.
Having a signal connected to the hard drive, and no power applied, at least in a traditional TTL or CMOS circuit, is not a good idea.
Since SATA is based on LVDS, this might not suffer from the typical CMOS or TTL problems, but I would investigate it a bit further.
They are cheap.
They don't invalidate your drives warranty.
Will do accomplish the exact same task.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
It's just a drive power switch. I was expecting the actual SATA connection to be switched not just the power to the various drives.
The pictures seem to be using a molex->sata power adapter, which doesn't support the 3.3v line. This means that some drives won't work with it.
Do people really think that Grub is that hard or this just another case of because we can.
A nice and simple mod, but do they still ship BIOSes that don't have a select boot disk option?
Like "Press Delete to enter BIOS setup, ESC to select boot disk."
Last time I installed Linux I was too lazy to disconnect the other OS's disks. Using Grub again, for the first time in years. Wish me luck...
This is a power switch. Nothing more. Certainly not a sata switch. As much as I love soldering.. I'll stick with grub for this one. Then I can at least share my media across OSes.
Can all fish swim?
I would like to see what terrible, terrible things happen when some idiot let loose near your computer decides that the knob on it looks weird and takes it for a spin. In the middle of a kernel compile.
And by terrible things, I mean manslaughter.
An active switch that could select a drive and optionally block write commands would even be better. Then you could make an image and turn on write protection.
And with this I could read the Linux drive in Windows. So I need a way to have both drives active, but change their device order. But for just reading Windows in Linux and not the other way around, it would be as simple as switching the Linux drive on and off and making sure it is always first when it's on.
now we need to go OSS in diesel cars
It's a neat hack, yes, but not really ideal. For all of the effort involved in setting up a switch like this, my solution of setting the first boot device to be the drive with my most frequently booted OS, and then just press F11 (on my board) to access the boot device menu if I want to boot to another drive is a lot easier.
Additionally, my method isn't restricted to just S-ATA drives. Not as cool, but a *tad* more functional...
I was expecting a switch that would let you switch the data cable between multiple drives. That way you could have all the drives on one port, and tell the BIOS to boot from that since it will always be the same slot. I don't see how this switch will stop errors like "Primary SATA Drive not detected" from showing up. Or how it would work in a system where you have to specify which SATA channel to boot from.
With a data cable switch you would only need one small drive for each OS (you could even use a solid state device for more speed) and there could be a couple separate drives for data that are shared between all of the operating systems.
Wow, this is a really amateur. They're even switching the ground leads (it would be better NOT to switch them). Here I though it would be an interesting article about how to properly switch SATA data signals and it's a C- grade power switch?
Big deal. Any idiot who can install a light switch should be able to think this up. Once again, slashdotter's don't know crap about electrical engineering.
Switching circuits should not try to draw power from data lines! And if power is not supplied, they will. Perhaps some systems are robuse (3.3V isn't much), but I would not count on all circuits not having some overheat path.
The design switches ground (Black) as well, instead of keeping it permanently connected. This means that if you use a non-bridging rotary switch (i.e. it does not short out neigbouring connectors when turning it, but has a short phase where all wires are insulated), you could kill disks when switching under power. This happens when +12V and +5V already (or still) have contact but ground does not. The effect is that -7V (a negative voltage) gets applied from Red to Yellow. Typical electronics have a tolerance of -0.5V on their supply lines and die very fast (miliseconds) if that is exceeded in negative direction.
The same can happen if your (bridging) switch gets a bit corroded and does not make perfect contact anymore. This is not so uncommon.
My bottom line is that these people have no clue what they are doing and you should under no circumstances copy this faulty design. If at all, then switch only Red and Yellow, but leave Black
allways connected at all devices. Not only is that safe, there is in fact no sane reason at all to switch Black. I can only conclude that the idea of the designers was to simply switch all wires, without any understanding of the consequences.
I think this solution is also overdone. I have XP and several Linuxes on a GRUB multi-boot on two computers. True, once or twice per year I need to use a KNOPPIX CD or memory stick to boot my system and reinstall the boot manager. Takes about 5 minutes each time. Not an issue at all.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
As this is Slashdot, I expected the article to be about an ATA over Ethernet switch that would let you build an array of drives to rival fibre-channel.
Now that would be interesting.
Unfortunately it was just another article meant more for digg.com
If I have many OSs and filesystems in my box, I would want to have access to everything from any OS. Linux supports NTFS, Windows supports ext3(after installing a driver).
This mod is pointless. You need 2 drives that you can only use one at a time. The amount of power you save negligible. And you would extend the life of your drives way more if you put on them a fan you got from free from the garbage dump.
Most of the comments here are negative. The criticisms about swappable drive bays being better and that ground should not be switched are all valid.
However, I think articles like this are good. More people should actually do stuff, even if they burn out a few harddrives or power supplies in the process.
This will be awesome for my 2 year old who loves to push buttons and flip switches.
Now if someone could come up with a way to turn off power to the motherboard with a simple button on the desk so the cat can get in on the fun too.
This article is a supe example of how having just a smidgen of knowledge can get you into deep doo-doo.
First of all they should not switch the two ground wires. If the switch disconnects those first, you have several amps of DC flowing back through the SATA signal cable ground wires and connector pins, which are not designed for this kind of current.
Gray smoke and major disk and motherboard damage is not out of the question.
Next they apparently chose the prettiest and most expensive switch in the most expensive catalog, without care to check it for current or make before break specs. So they paid $28 for the wrong switch. A simple $1.99 DPDT 5-amp switch from the hardware store costs less than a tenth as much and will be able to handle the current.
Lastly, this switch should have some sort of lock on it. Accidentally flipping it in the middle of a disk write would be disastrous.
Come to think of it, the SATA data cable ground lines may actually save the disk electronics in practice. Because completely without ground, you get -7V from red to yellow, a sure killer.
The question is of course how long they will last, as you rightly point out.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
stuff that matters?
how the hell does this matter to anyone except someone suffering from brain damage?
who the fuck would even do this? is the author fucked in the head?
I can easily predict the following scenario at my house:
Child: Daddy, What does this do? *CLICK*
Me (nearly simultaneously): NOOOOOOOOOooo
And the sound you now here is the computer crashing and me muttering curses under my breath...
Why not have BIOS set up to boot from usb as primary boot device, IDE/SATA/SCSI as second, and have an external usb drive with an on/off switch? You could then access your usb drive contents even if booting off your IDE/SATA/SCSI OS simply by turning the usb drive on once the bootup sequence has started.
The switch is just switching power, could be IDE drive or anything. Also they swith the ground wires, which is completely pointless. All you have to do is switch the 5V and 12V...
How does stuff like this make front page of slashdot?
http://www.thesataswitch.com/ The author's actual site. Easier to read, and no annoying mouse-over ads.
To think that all this time, I was simply hitting the key to get my BIOS boot device selection menu after installing the OSes I wanted individually!
I run Windows 2000 Professional (MSDNAA License) with CoLinux kernel 0.7.3 booting GNU Slackware 12.1
When my older Pentium 1 class box, which acted as a (software) RAID storage server's fan started making noise, I shut it down and tossed the hard drives in my desktop system, altered the CoLinux configuration file to give direct partition access to Linux (ONLY!) then copied and modified the /etc/md.conf
Runs like a champ.. Even have a second NIC in the machine which Linux uses exclusively (TCP/IP is not bound in Windows).
It appears as a wholly seperate machine on the LAN, serving the Samba shares under the same NETBIOS name the Pentium 1 system had, so no other machines on the LAN even noticed the change. I stood beside myself when the RAID came online with both disks available. The disks sleep 99% of the time and I just leave the PC on, logged off in Windows when I'm not using it.
Of course there are limits to what you can do with CoLinux, but not many.
-- AC
At a prior job, we used to use IDE hard drives in caddies. When we wanted to change the operating system, we'd slip out the old drive and slip in the new one.
No, I will not work for your startup