Saturday, June 28, 2008 by Kaushik Tutorials n Tips , Windows

Usually, when you buy any hardware the drivers come along with it on a disc. If you lose the driver disc you can always download the necessary drivers from the manufacturer's website. But what do you do when you are not sure of the manufacturer of the hardware? This is quite a possible situation and blogger Vinod Chandramouli provides an excellent trick to deal with it.

Every device has a Vendor and Device id associated with it. If you can find this ID, you can find the manufacturer. In Windows it's easy to find the vendor and device id.

1. Open Device Manager (Control Panel>System>Hardware>Device Manager)
2. The hardware whose drivers are missing will appear as Unknown device, so it's easier to locate the device.
3. Right click on the unknown device and click on Properties.
4. Under the Properties window click on Details tab and select Device Instance Id from the drop down box.
5. You should see a code similar to this
   
   PCI\VEN_8086&DEV_27DC&SUBSYS_30868086
   &REV_01\4&1E46F438&0&40F0
   


6. The portion of the code highlighted in RED is the Vendor ID and the portion highlighted in GREEN is the Device ID. In this example:
   
   Vendor ID = 8086
   Device ID = 27DC


7. Once you have obtained both the IDs, proceed to PCI Database. There you can either search for the vendor from the vendor ID or directly get information about the device along with the vendor name by searching with the device ID.

Great isn't it? Now you will never have to go hunting for correct drivers.

http://www.instantfundas.com/2008/06/how-to-find-drivers-for-unknown-devices.html

I used to be a big fan of RAID5, but lately, and for certain circumstances, especially home servers, I've become more of a fan of mirroring.  Here's why.

1. Both instances of major data corruptions I've had in the last 10 years or so have been caused by my CERC RAID (Dell re-branded Megaraid EIDE) controller!
2. If/when that controller dies, the RAID is useless and the data inaccessible.  With a software mirror, a) there is no controller and b) either disk Just Works stand-alone.
3. The 1u servers I've been using lately have room for 2 disks (minimum for a mirror) but not 3 disks (minimum for RAID5).
4. Software mirroring is cheaper in that you don't need a controller.  It's arguably more expensive since you lose half your disk space instead of N-1 as in RAID5, but with disks so large and cheap these days, the added flexibility and reduced complexity of a mirror is more than worth it.
5. It's possible to "clone" a system by yanking one of the mirrored disks and installing it elsewhere, then adding new blank drives to both systems and allowing the mirror to rebuild.
6. If you move software mirrored disks into a new server they should Just Work.  The same is true when using n external controller (until it dies), but that's not the case if using a motherboard-based controller, so watch out for that.  When the MB dies you can lose the board and your data.
7. Fewer drives cause less heat and power consumption.
8. Software mirroring is faster on writes than software RAID5, and possibly even hardware RAID5, depending on the controller, since RAID requires doing some math while mirroring is just sending the same plain or write to two places.

Now, having said all of that I don't think RAID5 is bad or inappropriate or anything.  I'm just saying that a software mirror is a really handy thing to use, especially at home.  I've also completely ignored RAID10, 01, 6, etc.  Those are all great for heavy duty production environments, but for home use these days I don't think you can beat a software mirror on Linux + LVM.

Also note that any/all RAID, including mirroring, simply provides disk failure tolerance.  It is not a substitute for proper and tested backups!  I like BackupPC but there's a lot of great backup software out there. See also: http://www.backupcentral.com/.