How to restore a failed Porticor RAID on Windows Server
Software RAID on Windows is usually very reliable. One reason for a RAID failure is if you restart an entire array within a short amount of time, and Windows cannot ensure that the array members are still in sync.
Don't panic! Let's try to analyse the current state of your Porticor disks RAID array and figure out how to fix the "Failed Redundancy" error you are seeing.
First and foremost: can you still access your data? Unless you are dealing with a very unlikely scenario where every one of your RAID disks failed, you should still be able to access the information and as such perform the most crucial step of all - backup your data.
Simple recovery: Open the "Storage" tab under "Computer Management" and see if both of your disks appear as "Online" but with "Failed Redundancy" error, e.g.:
Right click one of the disks and perform "Reactivate Volume". This will begin the mirroring and resynchronizing procedure. This is a rather lengthy process and may take a couple of days for especially large disks. Note that the time depends on the size of the disks, and not on the disk space in actual use.
Once this procedure completes, your RAID is back to being fully operational.
Advanced recovery: In case your scenario is not as easily fixable, let's go over some basics first.
Step 1: Make sure all the relevant Porticor Virtual Appliances which hosted the RAID are online and operational. Look under the "Protected File Systems" category and make sure the disks list "Available for secure use" as their status.
Step 2: Click "use it" and look for a string beginning with "--targetname ign...", e.g.:
Step 3: Make sure "iSCSI Initiator" reports this target as connected.
Step 4: Open the "Storage" tab under "Computer Management" and see if you can spot one of your previous RAID disks as "Foreign".
Here we see Disk 3 as "Foreign" and Disk 4 as "Online" but with "Failed Redundancy" error. This means that the system is missing crucial information about Disk 3, while Disk 4 is active and available, but no longer has the RAID safeguard as before.
Note: It is important to note that I will keep referring to Disk 3 (the "Foreign" missing disk) and Disk 4 (the "Online" active one) but in your system those numbers may wary.
Step 5: In case you spot one of your disks as "Foreign" perform "Import Foreign Disks" by right clicking it and selecting the appropriate option. This will result in the "Foreign" disk being restored to “Healthy” state and getting a new drive letter. Your "Online" disk should no longer report "Failed Redundancy" and be "Healthy" as well. The ambiguity of missing its RAID mirror is cleared, and they are now both available to us (albeit as different disks).
Unfortunately, in this scenario Disk 3 is no longer a mirror to Disk 4, and we need to rebuild the RAID by creating a fresh mirror to Disk 4. You can use a new disk or even reuse Disk 3. If you choose to do so, make sure you have a recent backup and Disk 3 is available and healthy.
Step 6: Delete the current volume on Disk 3, by right clicking and selecting the appropriate option. Once done, the disk becomes "unallocated":
Step 7: Now we can recreate our RAID. Right click Disk 4, choose "Add Mirror", and select Disk 3:
The system will begin with the mirroring and resynchronizing procedure. This is a rather lengthy process and may take a couple of days for especially large disks. Note that the time depends on the size of the disks, and not on the disk space in actual use. The following screenshot is taken mid-process and shows the current disk performance, Disk 4 is being read, and Disk 3 is being written into.
- This guide was tested using Windows Server 2012.