Redundant Disk Challenges
Articles and Tips: qna
01 Nov 2002
Q.
We have an unusual configuration on one of our large production servers. We have the following configuration:
Raid 1 - 2-9GB drives (SYS)
Raid 5 - 6-36GB Drives
NetWare Partition 75GB (75GB VOL1)
Free Space 100GB
This was the original configuration. It was done this way so we could migrate to NSS on the 100GB area. However, we decided to wait until Netware 6 before migrating this server to NSS and ran out of space on the original 75GB VOL1. Looking back, we should have used Server Magic or Portlock Storage manager (which we did not have) to increase the size of the NetWare partition. However, the following was done:
Raid 1--2-9GB drives (SYS)
Raid 5--6-36GB Drives
NetWare Partition 75GB
NetWare Partition 75GB (150GB VOL1 spanned across to NetWare Partitions)
Free Space 25GB
We thought this would be safe since it was done on the same RAID5 logical drive. But this weekend we lost a drive on our 150GB VOL1 (RAID 5) drive and VOL1 went down. NetWare 5.1 would not mount VOL1. We replaced the drive and rebuilt the RAID5 at the hardware level. NetWare 5.1 was then loaded and after VREPAIR corrected six errors and we were back in business.
Novell Technical Services (NTS) (first level) said it should have stayed up and the rebuild should have taken place with the operating system working (no down time). Is this a redundant configuration, or is there a flaw here? We are waiting on a call back from the hardware vendor. Wish we could have extended the NetWare Partition instead.
Not-So-Redundant Rudy
A.
Dear Not-So-Redundant: I will have to agree with NTS. I doubt that extending the NetWare partition would have done any better, as the raid adapter should have been on the fly recalculating the missing bits. If that wasn't happening, you were in trouble. If this was one of my systems, I would have swapped out the raid adapter before I put in a replacement disk to see if that fixed the problem. Having a Raid 5 that is only as redundant as raid 0 is worse than having no raid at all. Good luck with your implementation!
* Originally published in Novell AppNotes
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