[SOLVED] upgrading my array

[rcrh]

I'm running out of storage space and am about to upgrade one of the drives in my array.  But I know that the initial preclear & rebuild of the data could take a couple of days.  So I'm wondering if I can put the drive in a USB chassis, mount it, run the preclear, and then do the upgrade? 

 

I'm trying to minimize that period of time where I'm exposed to a failure without a complete back up.

 

I don't think it matters but my config is:

unRaid 5.0.6

processor: P4 of some sort

RAM: 4gig

drives: parity    4tb

          drive 1 - 4tb

          drive 2 - 4tb

          drive 3 - 2tb

          drive 4 - 2tb

          drive 5 - 2tb

          drive 6 - 2tb

          drive 7 - 2tb

 

parity, 1, 2, & 3 are on the mobo controller and the others are on a PCI card.  I'll be replacing drive 3 with a 3tb drive.

 

Thanks in advance to anyone who can help me mount the USB drive & run the preclear script on it.

 

[garycase]

The pre-clear script doesn't run against USB attached devices ... and even if it did it would take MUCH longer via a USB v2 interface.

 

A few other options ...

 

(1)  Use a spare computer ... if you have another computer you can use for that; just boot a free copy of UnRAID on that PC (don't assign any drives to it) with the pre-clear script on the flash drive; then run pre-clear on that.

 

(2)  Use the UnRAID computer.  Same as #1, except use the UnRAID computer.  Just shut down;  switch to another USB flash drive with the free version of UnRAID on it;  then disconnect one of your current drives and connect the new one; boot and run pre-clear.    The disadvantage of this is, of course, that the system is unavailable while you're using it to do the pre-clear.

 

(3)  Test the drive another way.  You can test the drive by connecting it to another PC via USB and then run a good disk test on it using a utility that will run on the PC.  WD's free Data Lifeguard for Windows is a good choice ... just run the quick test; then the extended test; then the complete write zeroes; and then repeat the extended test.

 

(4)  Just trust the drive.  Do NOT do ANY writes to your array during the replacement process ... you can then recover if there's an issue.    Run a parity check BEFORE starting and confirm there are no sync errors.    Now do the drive upgrade ... and then run a non-correcting parity check.    If there are no sync errors, everything's fine.    The reason for the non-correcting check is that if there ARE any sync errors, you can still rebuild the drive on another disk.

 

[dgaschk]

I think that pre-clear does work on usb attached drives. The SMART data may not appear but otherwise it should ok. It will be slow.

[itimpi]

I think that pre-clear does work on usb attached drives. The SMART data may not appear but otherwise it should ok. It will be slow.

That is my experience as well.

 

Having said that if you are using USB 3 the performance is not much slower than direct SATA connection.  With USB 2 it is painful if you are trying to preclear a large drive.

[garycase]

I had tried using pre-clear several years ago with a USB drive and it wouldn't work ... good to know the latest version does.    As itimpi noted, however, unless it's a USB v3 port it would be VERY slow.

 

... and if it doesn't access the SMART data via the USB bridge that's a major loss of data from the pre-clear.

 

[rcrh]

First, thanks all.  After reading this I got all kinds of cowardly and decided to get a little more manual in my upgrade.  I was removing a 2tb drive so I cleaned up data until I had over 2tb available.  Most of this space was gained by deleting things from the recycle bin.  Next I manually moved data from the target drive to the other drives.  Once it was empty I shut down the array, powered off the server and replaced the empty 2tb drive with the new 3tb drive. 

 

When I brought the server back up I select the new 3tb drive in that slot and expected unRAID to format the new drive & preclear it before coming back online. 

 

However, it didn't do that and just started a data rebuild.

 

Eight hours later I now have what I wanted but am left with two questions:

1) the 3tb drive was NTFS formatted: did I miss the reformat or was it not done, and

2) should I be worried that the drive wasn't precleared?

 

I've not put any data onto the drive so I'm at a perfect place to start over if I need to.

 

Thanks again.

[itimpi]

First, thanks all.  After reading this I got all kinds of cowardly and decided to get a little more manual in my upgrade.  I was removing a 2tb drive so I cleaned up data until I had over 2tb available.  Most of this space was gained by deleting things from the recycle bin.  Next I manually moved data from the target drive to the other drives.  Once it was empty I shut down the array, powered off the server and replaced the empty 2tb drive with the new 3tb drive. 

 

When I brought the server back up I select the new 3tb drive in that slot and expected unRAID to format the new drive & preclear it before coming back online. 

 

However, it didn't do that and just started a data rebuild.

That is expected behaviour.

 

Eight hours later I now have what I wanted but am left with two questions:

1) the 3tb drive was NTFS formatted: did I miss the reformat or was it not done, and

A rebuild leaves the rebuilt drive in the same format as the drive it was being rebuilt as.  The only difference would be that as this is a larger drive, at the end of the rebuild phase the file system would be expanded to include the whole drive.    What format was on the disk before the rebuild started was irrelevant as the rebuild works at the physical sector level, not the file system level.

2) should I be worried that the drive wasn't precleared?

A rebuild does not require that a disk be pre-cleared.  In the case of a previously used disk whether it was advisable depends on whether you think the disk was in a good state or not as all running the pre-clear script provides in such a case is a stress test/confidence check of the drive.

 

I've not put any data onto the drive so I'm at a perfect place to start over if I need to.

I would just get a SMART report for the drive.  If everything looks good it is not worth starting over.

 

Note that since the drive currently has no data on it, now might be a good time to switch the format to XFS (assuming it is not already in that format).  The process is to stop the array; click on the drive in the Main tab which gives you a dialog where the format can be change; restart the array which will now have an option to format the drive; format the drive to create the empty XFS file system on it.  The drive is now ready to have data copied back to it.

[rcrh]

itimpi, thanks for the great reply.  I appreciate all that info.

Since the 3tb drive going in wasn't new I decided to start over so i could run a preclear on it.  To do this I did the following:

1) stop the array

2) unassign the 3tb drive

3) run "new config" from the utility menu and wait for the parity to be rebuilt

4) run the preclear on the 3tb drive

5) add the drive to the array.

 

I'm at step three at the moment and I'll take this opportunity to start reading about xfs.  Although, I thought it wasn't available in version 5.x of unRAID.  I thought it was a version 6.x feature.

 

Thanks again.

[itimpi]

itimpi, thanks for the great reply.  I appreciate all that info.

Since the 3tb drive going in wasn't new I decided to start over so i could run a preclear on it.  To do this I did the following:

1) stop the array

2) unassign the 3tb drive

3) run "new config" from the utility menu and wait for the parity to be rebuilt

4) run the preclear on the 3tb drive

5) add the drive to the array.

That should work fine.

 

I'm at step three at the moment and I'll take this opportunity to start reading about xfs.  Although, I thought it wasn't available in version 5.x of unRAID.  I thought it was a version 6.x feature.

It is only available on v6.  Since we are in the v6 part of the forum I assumed that was what you are currently running

[rcrh]

It is only available on v6.  Since we are in the v6 part of the forum I assumed that was what you are currently running

Well aren't I an idiot!!

 

Maybe some nice moderator will move this to 5.x/general support forum.

 

Thanks again.

[garycase]

It is only available on v6.  Since we are in the v6 part of the forum I assumed that was what you are currently running

Well aren't I an idiot!!

 

Maybe some nice moderator will move this to 5.x/general support forum.

 

Thanks again.

 

Done 

 

... and no, you're not "... an idiot" => we all missed that as well, even though you very clearly noted that you were running 5.0.6 in your very first post.

 

[rcrh]

garycase,

 

ta very much.