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Forum Discussion
peteophoven
Jul 10, 2017Aspirant
Expanding RAID - failing
Dear Community. We have begun expanding the volume from 1.8 TB with three 1TB drives running in RAID X2. We purchased 3 x 4TB drives. The first 2 added just fine. Taking us to 6.4TB. I am tr...
- Jul 11, 2017
peteophoven wrote:
We started the volume with 3 X 1 TB drives.
OK. That's the same volume size as a single 2 TB drive (except you have redundancy).
Because your starting point was 1.8 TiB, your volume expansion ceiling is 9.8 TiB.
3x1TB + 3x4TB would give you a volume size of 11 TB (or 10 TiB),
The last drive expansion still fails because it would take you over your expansion ceiling (just barely, but still over).
Reformatting the drive won't overcome that. As I said above, you either need to do off-line expansion with ssh, or do a factory reset and restore the data from backup.
If you do a factory reset, you can switch to OS-6. Though not supported by Netgear, it doesn't have any known expansion limits.
StephenB
Jul 10, 2017Guru - Experienced User
What firmware are you running? I ask because of the "OS 6 on Legacy" tag on your post. That implies OS-6, but your post suggests something else.
Your 9 TB expectation isn't right - In your case you should end up at 8 TB total volume size (7.3 TiB).
That shouldn't be hitting any expansion limits with OS 4.2.
BTW, 2x4TB+2TB should have given you ~5.4 TiB Are you seeing 6.4 TiB now?
- peteophovenJul 10, 2017Aspirant
Thank you.
Yes to clarify it is a ReadyNAS Pro 6.
Firmware 4.2.28
Here is how the drives are currently setup:
RAID Level X-RAID2, 6 disks Showing 6466GB
Status: Redundant
Ch1: 927GB
Ch2: 927GB
Ch3: 927GB
Ch4: 3721GB
Ch5: 3721GB
Ch6: Indicates 3721GB but it keeps failing.
I'm thinking of pulling the drive. Restarting the unit and reinserting it?
- StephenBJul 11, 2017Guru - Experienced User
I thought you were replacing the 2 TB drives, not adding to them.
3x2TB + 3x4TB would give you a 14 TB volume size altogether. ("sum the drives and subtract the largest").
3x2TB + 2x4TB would give you a 10 TB volume size (9 TiB)
If you happened to start with a single 2 TB drive installed when you first set up the system, then the 8 TiB growth limit would be reached between 10 and 11 TB. I'm thinking that's what's happened.
If so, reinserting the disk won't help. You'd need to offload data, do a factory reset, and then restore. It is possible to do an off-line expansion with ssh, but you should still do a backup first if you want to attempt that.
- peteophovenJul 11, 2017Aspirant
We started the volume with 3 X 1 TB drives.
The volume was around 1800 GB.
We added a 4TB
and then another 4 TB to get us to where we are now - 6400 GB.
Its this last drive that isn't playing nicely.
I fear having to take the drive offline and reformat. It will be difficult to pull that off.
Highly utilized and maintained production server.
Thanks for your help.
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