Apologies if this is common knowledge, but I couldn't seem to find it.

 

I'm replacing my 1.5TB parity drive with a 2TB drive.  I'd like to minimize the amount of offline time of the array.  Will the array be unavailable to the network during the parity build?  Slow is one thing, but if it's offline for the 16 hours or so it takes to calculate parity, I'll have to schedule this kind of carefully.

Several months ago I replaced my 2TB parity with a 3TB parity drive. Yes, during that time I was still able to access my array normally. Placed the 2TB drive into the data array after. I was using unRAID 5 beta 12 or 13 at this point.

 

Recently (during the past week) I replaced a data drive that was going bad (giving lots of errors, but still working). During the rebuild of the data drive, I had full access to my array as well (even started my addons running on my cache drive during this).

 

My signature is up-to-date with my system information. Results on unRAID 4.x may be different, I've not used it.

Thank you.  I should have mentioned my version, 4.7 Pro, but I'm not sure that matters for this question.

This post leads me to believe there may be a difference in unRAID 4.x.

This post leads me to believe there may be a difference in unRAID 4.x.

Yeah, the info seems to be somewhat ambiguous.  Maybe I'll just simulate it in a VM and see what happens.

Array is only unavailable during new drive clearing on any version a sane person would still be using.

Array is only unavailable during new drive clearing on any version a sane person would still be using.

I re-read this and I think I get the double negate now.  Are you saying that the only time an array should be unavailable (barring errors / multiple broken drives) should be during a clearing of a new drive, but the array should be available under most other normal actions?  Unless you're on a very old version of UnRAID.

 

This is not new drive clearing, the drives have been pre-cleared on another machine (2x 2TB drives are being installed, one as a new Parity drive and the other as a data drive, the original Parity drive will become a data drive later, but data drive install is not part of this question.)

 

This question is asking if the array will be available for use while the new Parity drive is being built from existing data.

 

FYI: there are currently 6 total drives in the array, 5x data drives and a Parity drive; most are 1.5TB, one data drive is 1TB.

 

I have to assume that your mention of "any version a sane person would still be using" refers to some version very previous to 4.7?  But, also, since you're talking about clearing drives, that may not apply to this question anyway.

Yes, the only new/change/upgrade disk operation where the array is not available is during the clearing of a new drive.

 

I'm not sure about very old versions but it's been this way for years with 3.x and 4.x and 5.x versions.

 

Yes, the only new/change/upgrade disk operation where the array is not available is during the clearing of a new drive.

(WHEN BEING ADDED TO AN EXISTING PARITY PROTECTED ARRAY )

I'm not sure about very old versions but it's been this way for years with 3.x and 4.x and 5.x versions.

been that way in every version since 1.X.  It is only when adding a disk to an established array.  It is available when upgrading a drive or changing a disk EXCEPT when performing a parity-swap-disabled-disk procedure.

Ummm, no need for the silly big red letters. What I posted was correct. Newly added disks are not cleared when there is no parity disk.

 

Ummm, no need for the silly big red letters. What I posted was correct. Newly added disks are not cleared when there is no parity disk.

Yes, but less experienced readers could think the installation of a "new" drive to replace a failed drive will result in the array being taken off-line for hours.  That is not the case unless performing a parity-swap with a disabled drive.  (While parity is being copied, the array is off-line)

Ok, so, I've been using UnRAID for a while, but I don't always know all the terms being used here, such as "parity-swap with a disabled drive."

 

When I take the array offline, Change the Parity slot to the new, pre-cleared drive, and let it build Parity, will I still have access to the data?

Ok.  I built a VM and tested it and yes, it's accessible while building with the new parity drive.

 

Test scenario:

 

VMWare ESXi 4.1

UnRAID Image on IDE (built vmdk with an XP VM, modified "make_bootable.bat" with -f on syslinux)

LSI SAS for data drives

3x 2GB Virtual Disks

1x 3GB Virtual Disk

 

Built array with parity using 2GB virtual disks, confirmed accessible and writable.

Stopped array, replaced Parity Slot with 3GB Virtual Disk.

Started array with Parity build.

Array was available and writable during Parity build.

 

Solved.

I should have posted new disk, not new drive in the one post. If you assign a new disk location on the server then the array is not available while that new disk is being cleared. The disk will only be cleared if a parity drive is present.

 

There is a built-in method to replace a failed disk when the replacement hard drive is larger than the existing parity hard drive. First, unRAID will copy the parity data to the new hard drive and put it in the parity location and then unRAID will rebuild the failed disk on the old parity hard drive. The array won't be available during the copying of the parity data.

 

Otherwise, the array is always available when you replace disks.