Just a note to all your folks looking to do software raid: When you partition the drives, leave some space (1%) at the end of the drives unpartitioned. Try not to partition the entire drive.
A problem I ran into a month ago involved a RAID 5 array of 3 IBM "40GB" drives. One drive failed. I purchased a Maxtor to replace it... turns out the maxtor "40GB" drive is about 500MB smaller than the IBM drives.. because it was not the same size as the partition on the IBM drives I could not use it as a spare... The best way to deal with this is to anticipate that you might be replacing a drive with a slightly smaller one in a couple of years.. leaving 1% at the end of the drive is well worth avoiding the headache that comes with purchasing a drive and finding out it is slightly too small to be a replacement drive. I only had about 45 gig of data, so I shuffled data around and deleted some until I had less than 40GB of data... I copied this onto the new drive.. repartitioned the old drives, created a new raid superblock.. copied the data back.. then added the new drive to the array and rebuilt the array. What a mess. -matt On Fri, 4 Apr 2003, Andrew Jorgensen wrote: > Andrew Jorgensen wrote: > > Hans Fugal wrote: > > > >> I don't see why it wouldn't work, unless it was broken. That's the > >> purpose of mirror RAID. Of course, things need to be set up right and > >> you should be familiar with the raid tools... > > > > > > Okay, so I'm supposed to partition the spare to match the one that was > > lost, right? Is there an easy way to do that? Is it safe to just dd a > > few KB from the one disk to the other? If so, does anyone know how many? > > I felt like being dangerous so I went ahead and just let dd run for a > minute. Then I ran raidhotadd. My little array is rebuilding. This is > cool. Thanks Hans. > ____________________ BYU Unix Users Group http://uug.byu.edu/ ___________________________________________________________________ List Info: http://uug.byu.edu/cgi-bin/mailman/listinfo/uug-list
