Damaging and Restoring RAIDs in Windows 2000 Server

Materials:
Working complete PC
3 Additional IDE HDD's
Additional IDE cable
Student Diskette, "New Boot A Ver 2.0+"
Student CD-ROM, "Windows 2000 Server OEM"
Objectives:
The student will become familiar with:
The definitions and Concepts of RAID storage technologies,
Setting up software level RAID's on the Windows 2000 Server,
Preparing for a Disaster on Windows 2000 Server,
Testing and Recovering from a disaster on a Windows 2000 Server.
Competency:
The student will learn the definitions and concepts of RAID storage technologies and the configuration of software level RAIDs on the WIndows 2000 server. The student will begin to learn the concepts of disaster prevention, testing and recovery on the Windows 2000 Server.
Preparation - Simulating Damage to the RAIDs

For the purposes of conserving space on this website, a system has been set up in which the boot partition has been mirrored to Disk 1 and occupies about half of the drives. The other halves of the drives hold parts 1 and 2 of a RAID-5 whose third part is held on Disk 2. In this way the repair of both a mirrored boot drive and a RAID-5 holding the data files can be demonstrated here in a single tutorial. Here is the system prior to our sabotage:



We reboot the system to the bootable support CD-ROM for the classroom and "wipe" drive zero, overwriting it in entirety with zeros. This destroys not only the MBR and the data on the system/boot partition but also destroys the dynamic drive database held at the far end of the drive as well. Now the system will not boot at all since our boot drive the Master of the Primary ATA controller has been completely destroyed. We must use the bootable floppy diskette created in this exercise to boot the system and select the "Mirror" boot option when it appears on screen. The system boots to the log on screen and we log on as Administrator. This brings the system to the desktop and nothing seems wrong from this vantage point.

Procedures - Repairing the Damage to the RAIDs
  1. Opening the Disk Administrator however, immediately launches the Write Signature and Upgrade Wizard. We cancel this and a grave situation is presented in the Disks pane of the Disk Administrator. The original drive zero is an empty and inaccessible disk and the original disk that held the first part of the mirror and a part of the RAID-5 is listed as missing:



  2. The first step to restoring the system on to the blown away disk 0 will be to break the existing mirror. It should be noted that in a real world situation if the system had to be booted from the emergency boot floppy in this way and displayed this situation, then Disk 0 would have to be assumed unreliable. The first step would be to scan the system with the latest anti-virus. Even if this turns up nothing the drive should be removed and be partitioned FAT32 and be formatted. If this succeeds it would then be scandisked at the very least if not get a thorough inspection by a third party utility like Norton Disk Doctor. Moving right along, we assume that the drive has been thoroughly checked out and/or replaced and we now proceed with the repair process by right clicking on the functioning half of the mirror set and taking the "Remove Mirror" choice:



  3. This window appears asking which component of the mirror should be removed. The choice is obvious...the part on the "Missing" drive! Select it and click the Remove Mirror button:



  4. This message box appears giving you one last chance to change your mind...click "Yes":



  5. Here is the current situation at this point. Remember that with these Windows 2000 Dynamic Disks that all of the disks in the system are considered a "Disk group" and they all have information about each other. This is why the system must be reconstructed carefully and correctly here in Disk Manager or all data could be permanently compromised.



  6. Now we need to prepare the new Disk 0 for use. In a real world scenario we would assume that some catastrophe occurred to Disk 0. The system would have to be scanned by a completely up-to-date anti-virus and the latest Windows updates might have to be applied to avert security holes (in its current state the system would have to be taken off of the network briefly if Windows updates are to be skipped until the drives have been repaired). Once the old Disk 0 has been wiped and scanned or replaced then this procedure could continue at this point. Right click the drive and write a signature to the "new" Disk 0 (Click here to see how):



  7. Now right click it again and upgrade it to a dynamic disk(Click here to see how):



  8. The next phase of reconstruction of the system is to add the mirror back to the replica of the C: drive currently held on Disk 1 (the one we just booted the system to). Right click on this partition and select "Add Mirror...":



  9. Select Disk 0 as the drive to which this partition will be mirrored and click the "Add Mirror" button:



  10. After the system has "regenerated" the mirrored volume and reports it as "healthy" we can turn our attention to the RAID-5. Here is the current situation of the reconstruction process:



  11. By the way, files stored on the RAID-5 volume in the R: drive are currently accessible and can be copied off to a safe location perhaps on another system in the network while this work is carried out. Even though one part of the RAID-5 has failed, as long as the two others are functional (as they are here) all files on them can be accessed. This is the power of the RAID-5. Now right click on any portion of the RAID-5 volume and click "Repair Volume":



  12. In this case the only Disk available is Disk 0, if you had a choice be sure the correct disk is selected and then click the "OK" button:



  13. Here we see the RAID-5 regeneration process proceeding to build the lost information onto a volume partition on Disk 0. You should wait until this process is complete and reports the RAID-5 volume healthy once again before removing the "Missing" Disk which can be done now that no more volumes remain on it by right clicking it and selecting the "Remove Disk" option:



  14. Here is the situation now that all of the work is complete. All volumes and drives are completely restored to their former state. The system is fully recovered from the loss of the old Disk 0:



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