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Topic starter
I haven't yet bought the product. Before I do, I'm trying to better understand if it can do what I need. I haven't been able to find an online manual (though the videos were somewhat helpful).
I understand the "verify all disks" advice, I really do, and I agree with it. But the procedure for mirroring an existing large drive seems unnecessarily unwieldy and time-consuming, with two many advance backup and copying operations, so I'd like to get your reaction to an alternate scenario.
What I'd like to do is:
1) Certify two drives of the same size as the existing drive (one of them for eventual use as a rotating archival drive, as discussed elsewhere).
2) Introduce one of the new drives as a duplex partner to the current (unverified) drive, and let them partner up. (The data from the original drive is going to be only as reliable as it already is, no matter how I access it at this point, so I've already eaten whatever risk is involved.)
3) Once the drives are partnered, drop the original drive and replace it with the other certified drive; let them partner up again.
4) Meanwhile, certify the original drive (wiping it).
5) Once the mirroring in step 3 has run to completion, drop one of the two partners, archive it, introduce the original (now clean) drive, and let it partner up one last time.
Is there anything terribly wrong with that approach? It's no less time-consuming, but at least it's time I can be away from the shop doing other things, while my data remains continuously available for use by the shop machines. (Note that you don't NEED the third drive to make this work, I just wanted an archival drive for its own benefit.)
Also, a question: if the first drive is partitioned, will SoftRaid have any problems partnering it with a new mirror drive? (The partitions are all data volumes, not boot volumes.)
Posted : 08/10/2016 4:58 pm
The terminology you are using is slightly confusing to me, but I think you are OK.
If you have two volumes, SoftRAID can convert it to SoftRAID format, then you will need to make each volume a Mirror.
Here is what I think is the simplest way to get this accomplished:
(I am going to assume you can only connect two disks at a time, as if you can have all three connected, this can be simpler)
1. Certify the two new disks, then initialize each one with SoftRAID.
2. "Convert" either existing volume to SoftRAID.
(this will convert the entire disk to SoftRAID format)
3. "Convert" your existing volume to a Mirror, and select the secondary disk.
(Here is where if you can connect all three, you can add both at once)
4. You can use your machine while it rebuilds.
5. Convert the other volume to Mirror also, and it them rebuild.
5. When rebuild is complete, unmount both volumes, and remove the SECONDARY disk.
6. "Add Secondary disk", and add the third disk. repeat on the second volume.
Now you have a 3 disk mirror with two volumes.
Using two volumes is more complex, but you can do it.
Best Practice is to unmount each volume, wait a few seconds, then swap out the disk. You can do this while the computer is running if this is Thunderbolt, and generally also with USB.
Posted : 09/10/2016 5:14 am
Topic starter
The terminology you are using is slightly confusing to me, but I think you are OK.
Sorry, that's from my last paycheck job of 30 years ago where we manufactured continuous availability computer systems with mirrored drives standard.
(I am going to assume you can only connect two disks at a time, as if you can have all three connected, this can be simpler)
Are you implying I can run a RAID 1 drive with three mirrored partners at the same time? (I have a four-bay dock.)
5. When rebuild is complete, unmount both volumes, and remove the SECONDARY disk.
if I do that, I never get to certify the original drive. Is there a particular reason you suggest that I do it this way?
While we're on this topic… I downloaded the demo version of SoftRaid, and it's telling me that the original drive has an incipient failure (reallocated sectors: 105, failed reallocations: 105). Is the certification process likely to be able to remap and clear all those bad blocks? This drive has plenty of warranty time left -- do manufacturers honor this sort of indication as a warranty issue, even though the drive still appears to be operational?
Posted : 09/10/2016 1:02 pm
Lets try to handle all your questions.
SoftRAID supports up to 16 disks in a Mirror volume, so you can have more than 2 disks, yes. A disk can be safely stored off site and brought together to sync on a regular basis.
I was assuming only two drives connected at a time. I was not concerned with Certify disk, as that is not part of creating volumes, it is part of preparing the disks for use. Certify any disks before you try to use them in a volume.
Your original drive is failing. Do not use it. If it is under warranty, get it replaced.
Posted : 11/10/2016 2:06 am
