Clearing Confusion on AF Drives


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Also, from a more recent note from Tom, his new scheme will accept pre-cleared disks as it always has, but write a partition table to start the 1st partition at sector 64.  (good news for unRAID users, and me, since the existing pre-clear script I wrote would need no changes to specifically deal with sector 64)

 

Yes for 4.6.1 this is how I think it's going to be in final form: everything will work as it does now with two exceptions:

 

1. If a disk already is formatted with part. 1 starting sector 64, it will accept this as valid.

 

2. If a disk has a pre-clear signature, it will be formatted with part. 1 starting in sector 64, but in all other cases where unRaid wants to format the disk, it will start part. 1 in sector 63 like it does now.

 

Think this is a good compromise?

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Interesting. You're saying 4.6.1 will only format drives with the partition at sector 64 if they have been pre-cleared, I would assume by using Joe's pre-clear script. It works for me but you might have some users who aren't happy about having to download the script and then use the command line to run the script. Some users might want the AF support to be available by simply using the web interface.

 

Joe - I bet you're going to get requests to add a switch to your pre-clear script so it will erase the pre-clear signature from those people who want to burn-in their drive but still use sector 63.

 

Peter

 

 

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Interesting. You're saying 4.6.1 will only format drives with the partition at sector 64 if they have been pre-cleared, I would assume by using Joe's pre-clear script. It works for me but you might have some users who aren't happy about having to download the script and then use the command line to run the script. Some users might want the AF support to be available by simply using the web interface.

 

Joe - I bet you're going to get requests to add a switch to your pre-clear script so it will erase the pre-clear signature from those people who want to burn-in their drive but still use sector 63.

 

Peter

 

Quite a conundrum isn't it?

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Interesting. You're saying 4.6.1 will only format drives with the partition at sector 64 if they have been pre-cleared, I would assume by using Joe's pre-clear script. It works for me but you might have some users who aren't happy about having to download the script and then use the command line to run the script. Some users might want the AF support to be available by simply using the web interface.

Tom, how about respecting the partition starting sector on a pre-cleared drive?

If it is pre-cleared with the partition starting at sector 63, you need only set the partition type byte and use it. The partition will start at sector 63.

If it is pre-cleared with the partition starting on sector 64, you need only set the partiton type byte and use it.  The partition will start at sector 64.

 

I already have a an option in my newer version of the preclear-script to use sector 64 vs. sector 63 as the starting point, so users can select which they prefer.    I've just not yet published that version of the preclear script. 

Joe - I bet you're going to get requests to add a switch to your pre-clear script so it will erase the pre-clear signature from those people who want to burn-in their drive but still use sector 63.

Yes, but then it would not be detected as pre-cleared and you would be faced with the extended down time as unRAID cleared the drive.

 

I think my proposal is better.

 

If the disk is completely foreign or does not have a pre-clear signature starting on partition 64, then it can be partitioned at sector 63 as it is today.

 

This proposal would allow anybody who is pre-clearing the disk to specify they want sector 64 as the starting point, or if the new option is not given, to for it to start on sector 63.  (once we get to version 5 of unRAID I can possibly get the script to detect the unRAID version to set the default to 64)

 

Joe L.

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If the disk is completely foreign or does not have a pre-clear signature starting on partition 64, then it can be partitioned at sector 63 as it is today.

 

Wouldn't this cause disks like the WD EARS (no jumper) to be formatted incorrectly by unRaid? It seems like 64 should be the default in all cases. If someone wants to maintain backwards compatibility with previous unRAID versions they should then have to take special action.

 

We can't assume that all new disks will be pre-cleared unless this option is added to GUI and then required before the array will accept the disk.

 

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If the disk is completely foreign or does not have a pre-clear signature starting on partition 64, then it can be partitioned at sector 63 as it is today.

 

Wouldn't this cause disks like the WD EARS (no jumper) to be formatted incorrectly by unRaid? It seems like 64 should be the default in all cases. If someone wants to maintain backwards compatibility with previous unRAID versions they should then have to take special action.

 

We can't assume that all new disks will be pre-cleared unless this option is added to GUI and then required before the array will accept the disk.

Actually, it makes it identical to what it is today unless the user takes the time to pre-clear the disk with a starting sector of 64 for the first partition.  It simply gives an advanced option in the interim for those who are UCD compulsive and need the absolute fastest performance.  (remember, there are many users of EARS drive who did not install a jumper and are using the drives with no "noticeable" performance hit to their usage of the server. Even without a jumper, it is plenty fast enough for most users.)

 

However... I think the better "default" sector to start on if not pre-cleared, and not a "valid" MBR,  is sector 64.

 

Let me explain... if Tom wanted to make the default partition start at 64 when a valid partition does not currently exist (and the disk is not pre-cleared)  it would make things a tiny bit easier.  Then the only people who will have to do something unusual is those who already have a EARS drive with no jumper and who wants to get it re-built on sector 64.   They would have to un-assign the drive, start the array without it assigned, overwrite the MBR making it invalid (with a simple one-line command), then stop and re-assign the drive.  It will then be recognized as its own replacement and re-constructed on a partition starting on sector 64.  

 

Also... if Tom makes sector 64 the default if there is not an MBR that is currently valid, and the disk is not pre-cleared, then a person with an assigned EARS drive with a jumper installed need not do ANYTHING unless they are UCD compulsive.  If they are,they can stop, un-assign the drive, power down, remove the jumper, power up, start with it the drive un-assigned, stop the array, re-assign the drive, and start it once more.  It will not see a valid MBR and partition the drive for a sector 64 start.

 

My preference...

If pre-cleared with a sector 63 start, then the partition should be started on sector 63.

If pre-cleared with the partition starting on sector 64, then it should make the start of the partition be on sector 64.

Otherwise, I think sector 64 should be used if no "valid MBR" is present.

If a valid MBR exists, use it as it is. (valid=reiserfs and either sector 63 or 64 start for the only partition using the full size of the disk)

 

Oh well. enough lobbying (for this post)...   We'll soon see what he decides.

 

Joe L.

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Ok so I currently have 4 1TB WD Black drives (inc parity) along with a random 500 and 300 gb disk. I want to do a big upgrade and buy 3-4 2TB Drives, probably the EARS Drives and clear out those small discs and a few tb drives. So it looks like at this point I should WAIT until 4.6.1 comes out, then buy and install them without the jumper? I am in no hurry.  :)

 

Thanks!

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Ok so I currently have 4 1TB WD Black drives (inc parity) along with a random 500 and 300 gb disk. I want to do a big upgrade and buy 3-4 2TB Drives, probably the EARS Drives and clear out those small discs and a few tb drives. So it looks like at this point I should WAIT until 4.6.1 comes out, then buy and install them without the jumper? I am in no hurry.  :)

 

Thanks!

 

You should either get them soon, install the jumper, format them under the current version (<= 4.6) of unRAID, and plan to leave them like that forever.

 

Or you should wait, not install the jumper, and format in 4.6.1 once it comes out and is stable.

 

What you don't want to do is get them now, NOT install the jumper, and add them to the <= 4.6 version of unRAID.  That's the poor performance situation.

 

I'd suggest waiting if you don't need the space right away.  It eliminates the kludgy jumper that may cause you trouble in the future if want to do something else with the drive once you remove from the array.  And you'll also be contributing to the community by verifying that the sector 64 formatting is working in your rig.

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Action items for other AF drives:

  • To get maximum performance out of these drives (that do not have the WD style jumper), you should first backup any data you want to keep.  Then reformat the drive using version 5.0-beta3 by clicking the Format button in the webGui page for the disk.  This will position the start of partition 1 on sector 64.

So, SAMSUNG SpinPoint F4 EcoGreen 2TB (with the samsung firmware patch to fix the data loss bug) is now compatible with unRAID 5.0-beta3 ?

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Action items for other AF drives:

  • To get maximum performance out of these drives (that do not have the WD style jumper), you should first backup any data you want to keep.  Then reformat the drive using version 5.0-beta3 by clicking the Format button in the webGui page for the disk.  This will position the start of partition 1 on sector 64.

So, SAMSUNG SpinPoint F4 EcoGreen 2TB (with the samsung firmware patch to fix the data loss bug) is now compatible with unRAID 5.0-beta3 ?

Should be... as long as you can be sure the firmware was upgraded.  ;)
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I think I'm one of those OCD people that will want to remove the jumper (I plan on getting more of the 20EARS and having some with jumpers and some without will probably lead to confusion down the road where I might inadvertently erase something).

 

Tom alludes to running a few shell commands to make the conversion work.. Ideally, I'd like to be able to remove the EARS drive (w/jumper), remove the jumper, plug it back in and have unraid rebuild from parity on the same drive.

 

Possible without having to copy everything off and everything back? I'll accept a PM if we don't want to confuse people ;)

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You might have to do additional steps to re-enable the drive to function again after changing the status of the jumper. In the past there have been reports of needing to run a low level zeroing of the drive before it would function properly when changing the jumper after if was already in use.

 

Personally, I wouldn't frack with changing the jumper. Entirely too much headache with no benefit. If it's currently on, keep it on. If it's currently off, keep it off.

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Personally, I wouldn't frack with changing the jumper. Entirely too much headache with no benefit. If it's currently on, keep it on. If it's currently off, keep it off.

 

Words of wisdom.

 

If you are truly OCD and all your drives have to be the same, you can use some needle-nose pliers to remove the metal insert in some jumpers (so that just the plastic casing remains), and then 'jumper' all your drives regardless of make, model, or type.  Problem solved!

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I think I'm one of those OCD people that will want to remove the jumper (I plan on getting more of the 20EARS and having some with jumpers and some without will probably lead to confusion down the road where I might inadvertently erase something).

 

Tom alludes to running a few shell commands to make the conversion work.. Ideally, I'd like to be able to remove the EARS drive (w/jumper), remove the jumper, plug it back in and have unraid rebuild from parity on the same drive.

 

Possible without having to copy everything off and everything back? I'll accept a PM if we don't want to confuse people ;)

 

Sorry Raj and BRiT.  Have to agree with Stokes's sentiment.  With a mix of exactly the same model of drive, some with jumpers and some without, a person is bound to screw themselves up eventually.  Formatting a jumpered disk with sector 64 formatting option, or formatting an unjumpered with sector 63 formatting.  Although I can't in good faith recommend a mass reformatting - if I only had one or two I'd certainly consider it.  If I had more I might just always jumper the 2T EARS to keep the consistancy.  Then when the 3T EARS (or whatever) come out, start with the unjumpered drives.

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The next unRAID release is in final test and is almost ready for release.  There will be people who will experiment with removing the jumper, zero-ing the MBR, and then see if the drive performs normally.  So I'd say best thing to do is wait for those reports before risking data loss.

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Definitely interested to see how this all works out with previously jumpered drives.  Slightly different for me, but I don't think I had any true success taking a previously unjumpered EARS drive from my Drobo, jumpering it, and making it work with unRAID, despite many attempts to use dd to write zeros to the beginning of the drives.  I would agree with those saying to just leave the jumpers on if they are already on, simply to avoid a potential headache and drive downtime.

 

Was there any decision made on precleared jumpered drives?  I have two sitting in my box unused, and I think the ideal situation would be for them to start on sector 63, right?

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Definitely interested to see how this all works out with previously jumpered drives.  Slightly different for me, but I don't think I had any true success taking a previously unjumpered EARS drive from my Drobo, jumpering it, and making it work with unRAID, despite many attempts to use dd to write zeros to the beginning of the drives.  I would agree with those saying to just leave the jumpers on if they are already on, simply to avoid a potential headache and drive downtime.

 

Was there any decision made on precleared jumpered drives?  I have two sitting in my box unused, and I think the ideal situation would be for them to start on sector 63, right?

From messages from Tom, it is my understanding they will be respected as pre-cleared, and YOU will be able to select via a new setting where to start the partition.   So... you would want to select the non-advanced-format setting, which will normally start on sector 63, which because of your jumper will actually be on physical sector 64.   (Confused... ??? )

 

If you had pre-cleared them without the jumper, then you would want to enable the advanced-format setting, which would start the partition on sector 64.

 

Joe L.

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I am currently in the 11th hour of preclearing a 2TB EARS w/ the jumper.  Should/can I re-preclear it without the jumper?

 

The version of preclear that will support sector 64 partitions is not out yet.

 

Even if it were, you might want to consider proceeding with preclear as you are, with stable, proven versions of preclear and unRAID.  It will take some time for the new version to come out, be verfiied by the community.  Likely (if history is a guide) there will be a few issues found, that will take time to correct.  I honestly would not expect 4.7 to be released until sometime in mid to late February (and Murphy often proves me an optimist!).  If you actually want to use these new drives, just keep doing what you're doing and upgrade when the time is right.

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I honestly would not expect 4.7 to be released until sometime in mid to late February

 

No way man, this will be a short cycle.

 

What I was trying to say is that it would take some time to run those the release candidate testing processes and for the final version to be released.  Maybe mid to late Feb is pessimistic, but I'm usually proven to be an optimist in the end!  Looking forward to be proven wrong. :)

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