Just to confirm


mrbilky

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So I've read the FAQ on moving/adding disks to the array seems simple enough I currently have dual parity which I want to reduce to a single parity drive so should I take down the 2nd parity disk add/move drives to my liking then what format the 2nd parity drive so it can be added as a data disk in the array then do a parity check? And while I have your ear is there any performance loss/gain by using an HBA over native SATA ports on the mother board I have an LSI 9211-8i P20 and have 8 data drives and 1 parity and 2 Cache ssd's is there a preferred configuration I should shoot for? as always appreciate any input before I blow something up oh and I have one of those cheap HBA's with 2 sata ports I believe it is a marvel chipset and have read issues about them being flaky could the ssd's run on it without issue

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11 minutes ago, mrbilky said:

then what format the 2nd parity drive so it can be added as a data disk

How would you format the 2nd parity drive? You must let Unraid format any drive it will use in the array AFTER it adds it to the array.

9 minutes ago, mrbilky said:

So I've read the FAQ on moving/adding disks to the array

Do you have a link to that? I don't recall anything that discussed moving/adding disks. Moving disks and adding disks are not at all similar.

 

I think we'd better get things spelled out step-by-step since your 1st sentence is a bit vague and even wrong in spots.

 

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2 hours ago, mrbilky said:

I read this and added that i wanted to add some drives as well just to make sure i don't mess anything up so i don't need to format the second parity? I thought i had to format it with UD

http://lime-technology.com/wiki/index.php/FAQ#Can_I_reorder_my_drives_within_my_array.3F 

That link specifically says you shouldn't add or remove drives at the same time because you will invalidate parity. So, you can do what that link says, but you must add the new data drive (formerly parity2) separately.

 

Now on to an explanation of what happens when you add a disk to a new data slot.

 

If you add a disk to a new data slot, and that disk hasn't been precleared, Unraid will clear it so parity remains valid. Then after that, since it won't have a filesystem, Unraid will let you format it. I don't see any point in preclearing since presumably the disk doesn't need further testing, so you might as well let Unraid clear it.

 

Formatting a disk in UD in order to add it to a new data slot would be totally pointless since Unraid would clear it anyway.

 

Many people seem to have very vague ideas about the difference between a clear disk and a formatted disk, and indeed what format does.

 

A clear disk is a disk that has only zeros on it. It can be added to an array without invalidating parity because those zeros have no impact on parity.

 

Format is a write operation. It writes an empty filesystem to the disk. The only part of the disk that it writes is just enough to represent an empty top level folder in the format of the filesystem. All the rest of the disk still has whatever bits were there before, whether they were parity bits as in your case, or they were the bits of files from when the disk was used before to hold data in whatever filesystem was there before.

 

When Unraid formats a disk in the array, it updates parity just as it does for any other write operation. So Unraid must format the disk while it is in the array or parity will be invalidated.

 

This is also why formatting a disk is NEVER part of a rebuild. If you format a disk in the array, then attempt to rebuild it, all you will get is a disk with an empty filesystem, because parity has been updated to agree that the disk has an empty filesystem.

 

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OK, enough with the theory. Take a screenshot or printout of Main - Array Devices. You must have a record of the serial numbers of all disks in order to do the next steps.

 

Go to Tools - New Config and Retail All. It will then let you change your disk assignments however you want and optionally rebuild parity. In order to maintain parity, we can't add or remove any disks at this point, but you can change the order of your data disks however you want.

 

Be sure to Unassign Parity2, and be especially sure that you don't change the assignment of Parity. If you accidentally assign a data disk to the parity slot you will lose that data.

 

Check the box saying parity is already valid, and start the array. That should get you to a single parity array with your data disks reordered as you want.

 

Let us know if you have any questions about this part, and post a screenshot when you have completed it.

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17 hours ago, trurl said:

OK, enough with the theory. Take a screenshot or printout of Main - Array Devices. You must have a record of the serial numbers of all disks in order to do the next steps.

 

Go to Tools - New Config and Retail All. It will then let you change your disk assignments however you want and optionally rebuild parity. In order to maintain parity, we can't add or remove any disks at this point, but you can change the order of your data disks however you want.

 

Be sure to Unassign Parity2, and be especially sure that you don't change the assignment of Parity. If you accidentally assign a data disk to the parity slot you will lose that data.

 

Check the box saying parity is already valid, and start the array. That should get you to a single parity array with your data disks reordered as you want.

 

Let us know if you have any questions about this part, and post a screenshot when you have completed it.

Thanks Trurl I have brought down parity2 and put it into the array as disk5 and all is good Now I can add 3 new disks and reassign sata ports maintaining parity1 position? I purposely left parity1 as the seagate drive since its the only one I have to make it easily identifiable805754834_ScreenShot2018-12-15at8_22_53AM.thumb.png.5db9128439f3ea61cd3c3e417d2553be.png

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1 hour ago, mrbilky said:

Thanks Trurl I have brought down parity2 and put it into the array as disk5 and all is good

It seems like you jumped ahead and put parity2 in as disk5 without checking back with us. How exactly did you do that? Of course you could have done it as part of the New Config, but it would have invalidated parity. Did you add it in afterwards and let Unraid clear it?

 

1 hour ago, mrbilky said:

Now I can add 3 new disks and reassign sata ports maintaining parity1 position?

Is this a question? If so maybe this is the answer:

 

Unraid only cares about the disk serial numbers when keeping track of disk assignments. It doesn't care about ports.

 

 

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1 hour ago, trurl said:

 Did you add it in afterwards and let Unraid clear it?

 

Unraid only cares about the disk serial numbers when keeping track of disk assignments. It doesn't care about ports.

 

 

Yes I added afterwards and all is running good thanks for the help not going to worry about sata port assignment just going to add drives accordingly

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Just an update and a thank you all went well I did a new configuration to put the drives in the order I wanted them in and went to bed while it ran the parity check all is good no errors and all data and drives appear correctly, I do have one question though I noticed my ram is hovering around 40% from a previous 20% is that because I added 3 new drives to the array

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1 hour ago, trurl said:

Of course we have no evidence or anything to work with regarding what it was doing before. Maybe it will settle out. Simply adding drives should not matter.

Yep not sure when it started I guessed it was from adding the HBA but I have very little experience with linux and networking stuff I've been winging it and got away with it for some time but sometimes it catches up to me, I'll figure it out sooner or later appreciate your help don't think I would have found the "tools, new config, preserve current assignments without a few more days and allot more reading sometime information overload gets ahold of me, thanks again!

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