Software RAID Level Migration
- Thread starter enigmo
- Start date
I know, but the problem is there is no backup. I know, I know, it's probably a very awful thing to do on the face of it, but everything else I have is backed up to offline, external drives and I now have maybe 8 or 9 1TB+ USB and FW disks for the job, just not for this volume.
Prolly best I explain: This is 2x3TB disks in mirror and would like to drop in a 3rd disk and make it RAID5 to extend capacity. It's an archive of my DVDs for feeding my media box, so none of the data is irreplacable, it would just be a hassle and not an awful one at that cos it would force me to re-encode the older rips as MP4 rather than AVI, but that's another task for another day. I was just hoping that seeing as it is possible to migrate RAID levels on hardware controllers with (theoretically) no data loss, although of course a backup is absolutlely advisable, and Windows RAID implementation is so common and understood there may be a way of doing it here. The obvious riders being: With no backup if anything went wrong I would lose my data and that is acceptable in this case, and it being a software RAID it would take days to do, and that too is acceptable.
I also realise that if I got a 4th 3TB disk I could backup the current mirrored array to one of them, destroy the current mirror and create a 3 disc RAID5 array, copy back and extend to the 4th disk for an even larger RAID5 array, but that would mean buying two new 3TB discs rather than one, and that's more cash...
Prolly best I explain: This is 2x3TB disks in mirror and would like to drop in a 3rd disk and make it RAID5 to extend capacity. It's an archive of my DVDs for feeding my media box, so none of the data is irreplacable, it would just be a hassle and not an awful one at that cos it would force me to re-encode the older rips as MP4 rather than AVI, but that's another task for another day. I was just hoping that seeing as it is possible to migrate RAID levels on hardware controllers with (theoretically) no data loss, although of course a backup is absolutlely advisable, and Windows RAID implementation is so common and understood there may be a way of doing it here. The obvious riders being: With no backup if anything went wrong I would lose my data and that is acceptable in this case, and it being a software RAID it would take days to do, and that too is acceptable.
I also realise that if I got a 4th 3TB disk I could backup the current mirrored array to one of them, destroy the current mirror and create a 3 disc RAID5 array, copy back and extend to the 4th disk for an even larger RAID5 array, but that would mean buying two new 3TB discs rather than one, and that's more cash...
Soldato
- Joined
- 11 Oct 2008
- Posts
- 3,833
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- London
3 x 3TB disk RAID5?
You will lose your data. Do not even consider it.
Rebuild times will be way too long, and there is a good chance you will have an Unrecoverable Bit Error anyway.
Think about it like this:
If you set this system up, and in 18 months you lose all your data. Everything. Gone.
How much would you pay to not have to rip all those DVDs and music again? £100? £200? £1000?
If you spend the money now, you can avoid that situation completely.
Look seriously at RAID6 (or the ZFS equivalent) as a minimum.
You will lose your data. Do not even consider it.
Rebuild times will be way too long, and there is a good chance you will have an Unrecoverable Bit Error anyway.
Think about it like this:
If you set this system up, and in 18 months you lose all your data. Everything. Gone.
How much would you pay to not have to rip all those DVDs and music again? £100? £200? £1000?
If you spend the money now, you can avoid that situation completely.
Look seriously at RAID6 (or the ZFS equivalent) as a minimum.
