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Forum Discussion
adiamond2
Nov 19, 2016Aspirant
RN104 added 2 disks to raid 1 system. Don't know what it's doing
I had 2 disks in it as Raid 1. I tried to read search the community for what would happen if I added another pair of disks. Frankly, I found it entirely confusing (should there not be a manual for ...
- Nov 20, 2016
When you go to the third disk, it converts the volume to RAID-5.
That gives you protection from a single disk failure. Total capacity is the sum of the disks minus the largest.
For instance, if you started with 2x4TB and now have 4x4TB, the volume grows from 4 TB to 12 TB. The NAS reports the 12 TB in TiB (1 TiB = 1024*1024*1024*1024 bytes), so it will show 10.9.
StephenB
Nov 20, 2016Guru - Experienced User
When you go to the third disk, it converts the volume to RAID-5.
That gives you protection from a single disk failure. Total capacity is the sum of the disks minus the largest.
For instance, if you started with 2x4TB and now have 4x4TB, the volume grows from 4 TB to 12 TB. The NAS reports the 12 TB in TiB (1 TiB = 1024*1024*1024*1024 bytes), so it will show 10.9.
- adiamond2Nov 20, 2016Aspirant
So, if I undertand you correctly, given I had 2x 2TB disks (in a raid 1), and I added 2x 4TB disks the new thing will look like one big 2+2+4=8GB volume?
So, is there a document that I missed that explains what the result will be if you add or replace disks given a particular starting configuration?
Thanks
- StephenBNov 20, 2016Guru - Experienced User
adiamond2 wrote:
So, if I undertand you correctly, given I had 2x 2TB disks (in a raid 1), and I added 2x 4TB disks the new thing will look like one big 2+2+4=8GB volume?
Well 8 TB, but otherwise correct.
When you replace disks, you can either replace them with one that's the same size, or replace them with one that's at least as large as the biggest disk already installed.
Similarly, when you fill an empty slot, you need to add a disk that's at least as large as the biggest disk installed.
There is an XRAID calculator here: http://rdconfigurator.netgear.com/raid/index.html However, it doesn't clearly state the two constraints above. FWIW, there are other constraints with OS 4.2 and OS 5 ReadyNAS.
- coloattyNov 20, 2016Luminary
Chapter 2 of the ReadyNAS OS 6.6 Software Manual discusses volume configuration. The "Software Manual" can be downloaded from the ReadyNAS OS 6 User Guides and Documentation page.
- adiamond2Nov 20, 2016Aspirant
re:Chapter 2 of the ReadyNAS OS 6.6 Software Manual discusses volume configuration. The "Software Manual" can be downloaded from the ReadyNAS OS 6 User Guides and Documentation page.
I looked at it before. Yes, it kind of discusses volumes but, unless I'm missing it, what it doesn't do is say is what it will do if you (e.g. me) add disks to an existing setup.
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