[Ham-Computers] RE: RAID 1 Questions

[Hsu, Aaron (NBC Universal)]

Jim,

Robert explained it quite well - in short, RAID (except RAID-0) is designed keep a system up and running in case of a drive failure.  GHOST (and other "backup" programs) is a method of keeping an archive of past data, be it for data recovery or historical purposes.  "Mission critical" business servers usually use both, often with multiple levels of RAID for "extreme" continuous up-time or speed (such as RAID 5/1 or 5/0).

With RAID-1, the RAID controller will read data off a "primary" drive when the OS requests data, and, it will write data to both drives when the OS needs to write data.  This is why RAID-1 is called "mirroring" - essentially, both drives are identical when it comes to the data.  In fact, they're usually identical to the sector level.  The simultaneous writes occur independent of the OS - the RAID controller handles it (unless the RAID is software-based) - so the OS is usually oblivous to the fact that it's a RAID volume (it really doesn't care).  As far as the OS is concerned, it sees a single "logical" volume and that's all that matters.

Interesting that your Dell came configured as RAID-1 - did you order it that way?  Most systems that have the "return to factory config" option have a hidden partition with the factory image.  When invoked, the system will re-image the primary boot drive with the factory image that's in the hidden partition.  If both drives are still configured as RAID-1, then both drives will still continue to work as a mirrored set.  However, if you "break" the RAID set and configure the drives to work independently, then you'll have two drives to work with.  And, when you invoke the system restore process, it should restore the OS to the "primary" drive and you'll be able to use the other drive as a second drive - you may need to format it first as it will still contain the data from the RAID-1 volume.

And, as far as GHOST 10 not being supported anymore...so what?  Lots of people use older software - as long as it works, why not use it?

73,

  - Aaron, NN6O



-----Original Message-----
Sent: Saturday, October 25, 2008 9:10 AM
Subject: [Ham-Computers] RAID 1 Questions

How do you use RAID 1?   I Googled RAID 1, and understand it backs up your C drive to a second internal drive of the same size.  Does it run automatically, or do is there a menu somewhere?  If you need to recover, what do you do?

My Dell E510 is set up for RAID 1 - I'm not sure why since it came with Norton Ghost 10.  It has the option to return to original factory settings if F12 is pressed during startup, the app. and image are on their own "drives" and the RAID configuration may be provided so the user won't tamper with them.  I wanted to add an extended partition and was unable to do so.

I'm having problems with this computer (not shutting down properly, not printing, etc.) and am thinking of installing a new drive and making a clean installation, and am wondering whether to use the RAID 1 configuration.  Norton Ghost 10 is no longer supported by Symantec so I'll probably not use it.

Jim