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codo1234

best way to change parity disk?

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want to upgrade my Parity disk.

what is the best way to change it?

all my disk after preclear already, dont have free slot to connect to new disk.

 

can i do this?

1. Perform parity check

2. Shutdown server

3. Remove current parity drive and connect the new one

4. Turn system back on

5. System will indicate an error in that the parity disk is not connected, so I assign the new 6TB drive as the parity drive

6. do pre-clear to the new disk

7. Start the array and allow it to rebuild parity  

 

?

 

 

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11 minutes ago, codo1234 said:

Step 1 should complete with 0 errors before you proceed.

want to upgrade my Parity disk.

what is the best way to change it?

all my disk after preclear already, dont have free slot to connect to new disk.

 

can i do this?

1. Perform parity check

2. Shutdown server

3. Remove current parity drive and connect the new one

4. Turn system back on

5. System will indicate an error in that the parity disk is not connected, so I assign the new 6TB drive as the parity drive

6. do pre-clear to the new disk

7. Start the array and allow it to rebuild parity  

 

?

 

 

Make sure that Step 1 has 0 errors before you proceed.

Step 6 is probably not needed as the parity rebuild is a good confidence check and it is not necessary to preclear the parity disk as the rebuild process overwrites every sector anyway..

You also want to keep the old parity disk intact until step 7 completes just in case you have a data drive failure while building the new parity.

Edited by itimpi

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4 hours ago, itimpi said:

Make sure that Step 1 has 0 errors before you proceed.

Step 6 is probably not needed as the parity rebuild is a good confidence check and it is not necessary to preclear the parity disk as the rebuild process overwrites every sector anyway..

You also want to keep the old parity disk intact until step 7 completes just in case you have a data drive failure while building the new parity.

Also, it is impossible to clear a disk you have already assigned. But if you haven't started the array yet the the assignment hasn't been recorded.

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4 hours ago, itimpi said:

Make sure that Step 1 has 0 errors before you proceed.

Step 6 is probably not needed as the parity rebuild is a good confidence check and it is not necessary to preclear the parity disk as the rebuild process overwrites every sector anyway..

You also want to keep the old parity disk intact until step 7 completes just in case you have a data drive failure while building the new parity.

if i don't have 0 errors? what do i need to do?

id everything going well, how i do the swap with the old parity disk with one of the array disks? 

 

@trurl - thank you!

 

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13 minutes ago, codo1234 said:

if i don't have 0 errors? what do i need to do?

Is this a hypothetical question or do you have errors? The only correct answer for a parity check, whether now or any other time, is exactly zero and if it isn't you need to try to figure out why and do it over.

 

13 minutes ago, codo1234 said:

id everything going well, how i do the swap with the old parity disk with one of the array disks? 

Since you don't mention having a disabled data disk then I assume you don't. If that is the case then we won't talk about a "swap" since that usually means trying to exchange a good parity disk for a bad data disk and replacing parity with a larger disk all as one "operation".

 

Please confirm that you don't have a disabled data disk because if you do then everything we have said above doesn't apply and we need to talk about the parity swap instead.

 

If you don't have a disabled data disk, then you just need to do each replacement one at a time.

 

When you have finished rebuilding parity, do another parity check to confirm.

Replace data disk with old parity and assign it.

Start the array to rebuild data then do another parity check to confirm.

 

Really we should have probably asked for diagnostics so we could confirm all your disks are in good health. Are there any SMART warnings for any disk on the Dashboard page?

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1 hour ago, trurl said:

Is this a hypothetical question or do you have errors? The only correct answer for a parity check, whether now or any other time, is exactly zero and if it isn't you need to try to figure out why and do it over.

 

Since you don't mention having a disabled data disk then I assume you don't. If that is the case then we won't talk about a "swap" since that usually means trying to exchange a good parity disk for a bad data disk and replacing parity with a larger disk all as one "operation".

  

Please confirm that you don't have a disabled data disk because if you do then everything we have said above doesn't apply and we need to talk about the parity swap instead.

 

If you don't have a disabled data disk, then you just need to do each replacement one at a time.

 

When you have finished rebuilding parity, do another parity check to confirm.

Replace data disk with old parity and assign it.

Start the array to rebuild data then do another parity check to confirm.

 

Really we should have probably asked for diagnostics so we could confirm all your disks are in good health. Are there any SMART warnings for any disk on the Dashboard page?

 

first, i attached the diagnostics zip file. i dont have disable disk.

for the Smart warning:

Disk 3 - 199 - UDMA CRC error count (Raw Value 11725)

Disk 1 - 199 - UDMA CRC error count  (Raw Value 3)

Disk 2 - 5 - Reallocated sector count (Raw Value 1320)

           - 187 - Reported uncorrect      (Raw Value 11)

Disk 4 - 199 -  UDMA CRC error count (Raw Value 59795)

 

Thank you @trurl

 

homenas-diagnostics-20190111-2009.zip

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CRC errors are usually a connection problem but they may have happened in the past. You can acknowledge by clicking on the warning indicator and it will warn you again if they increase.

 

I assume disk2 is the one you plan to replace with the old parity disk. If not it should be.

 

So where are you at the moment. Have you completed the initial parity check?

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connection problems - need to buy new cables?

before i wanted to change disk 3 (its 1Tara) but now - i assume that i need to change disk 2, from what you wrote.

 

the parity check still running (57%,speed - 72.5 MB/sec) , i do every saterday, so last check 6 days ago - everything was ok, i assume it will be now also.

 

 

Edited by codo1234

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@trurl so, the parity check completed 

Duration: 15 hours, 31 minutes, 32 seconds. Average speed: 71.6 MB/sec

 

what now? 

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13 hours ago, codo1234 said:

@trurl so, the parity check completed 

Duration: 15 hours, 31 minutes, 32 seconds. Average speed: 71.6 MB/sec

You left out the important part of your parity check results.

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On 1/13/2019 at 2:58 AM, codo1234 said:

what now? 

Replace old parity with new parity disk, assign new parity, and start array to build parity on the new parity disk.

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15 minutes ago, trurl said:

Replace old parity with new parity disk, assign new parity, and start array to build parity on the new parity disk.

 did it, when i wrote 0 errors, its after the changing parity disk.

now i mean - how i change disk from the array, with the old parity disk? 

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Shut down the server.  Remove old drive.  Set it aside.  Install new drive.  Restart the server.  If array starts, stop it (Main tab, Array Operation).  Assign old parity disk to the vacant array spot.  Start array, should start to rebuild that disk.  (If you should get a prompt to format the new disk STOP!!! You have a problem.)    

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and what happens to data in this disk, when i remove him that and he part of the share Media? (in share of 3 diffrent disk)

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1 hour ago, codo1234 said:

and what happens to data in this disk, when i remove him that and he part of the share Media? (in share of 3 diffrent disk)

When you remove the disk it is emulated from the parity calculation using parity PLUS ALL other disks. That is what Unraid parity is all about.

 

Note that I said parity PLUS ALL other disks. None of the disks by themselves have the data, but it is still in the array, from the parity calculation.

 

With that disk removed, you can still read and write the emulated disk. Reading gets the data from the parity calculation by reading all other disks, and writing updates parity from the parity calculation by reading all other disks and the data to be written.

 

When you assign another disk to that slot, all that data will be rebuilt onto the replacement, from the parity calculation.

 

Parity isn't magic or even very complicated. Here is a wiki if you want a better understanding:

 

https://wiki.unraid.net/UnRAID_6/Overview#Parity-Protected_Array

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Thank you, going in the weekend read it and follow by your instructions.

one more question that i found several diffrenet answers, that not link to this subject, but i dont want to open a new thread for this:

before 2 weeks i installled first time cache drive (Samsung SSD 840 120GB - not big).

i have Download share (its only 1 disk in the array).

i have the Appdata folder that i configure in the same disk.

i followed this awsome guy Youtube video , and for the AppData settings did "Use cache disk: Prefer".

i had problems after, with Transmission app, that after i did reset to the server, some torrents disappear from transmission/web/ but still in the Incomplete or complete folders of the app -->i need again to add this torrents to transmission, and then they recheck.

 

i need to delete the Appdata folder, set it to Cache drive, some places said that i need to change  :"Use cache disk: Prefer" ----> "Use cache disk: Only".

what is the right way? i also read already the Wiki about cache drive.

because when Transmission app is working, Disk 3 (download share) and Parity disk are spin up, and the cache drive is sometimes spun-down or spin up.

 

Thank you 

 

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38 minutes ago, codo1234 said:

i need to delete the Appdata folder, set it to Cache drive, some places said that i need to change  :"Use cache disk: Prefer" ----> "Use cache disk: Only".

what is the right way? i also read already the Wiki about cache drive.

There is not a 'tight' way - it depends on how you want to run!

 

With cache disk: Prefer then the 'mover' will try and move any files that belong to the share from the array to the cache.  Also the system will try and create new files on the cache drive, and only overflow to the array if there is not room on the cache drive.  With it set to cache disk:Only then mover ignores any files on the array (i.e. they stay there) and all new files are written only to the cache.

41 minutes ago, codo1234 said:

because when Transmission app is working, Disk 3 (download share) and Parity disk are spin up, and the cache drive is sometimes spun-down or spin up.

This sounds like expected behaviour.    If a file already exists on the array drive then that is the one that is used (and updated).    Only if you add a new file would it be written to the cache drive and later (assuming you have Use Cache:Yes set) moved to the array.   The cache drive could be spun up either because a new file is involved, or because you have your docker image file there and it is being accessed by a container.

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Also, mover won't be able to move an open file. Since you just added cache it is likely some cache-prefer shares are at least partially on the array. And checking the diagnostics you posted on Friday I see that it is so. Those (old) diagnostics indicate you have plenty of room on cache for these next operations. If that is not still the case post another diagnostic and we can work something else out.

  1. Go to Settings - Docker and disable the docker service. Do the same for Settings - VM Manager if you use that.
  2. Go to Main - Array Operation, click Move Now and wait for it to complete.
  3. Go to Shares - User Shares and click on Compute All. Wait for the results.

After all that, ideally the appdata and system shares should exist only on cache, and all other shares should not have any contents still on cache.

 

If everything looks good re-enable dockers (and VMs if used).

If not then come back and we will see what needs additional attention to detail.

 

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5 hours ago, trurl said:

Also, mover won't be able to move an open file. Since you just added cache it is likely some cache-prefer shares are at least partially on the array. And checking the diagnostics you posted on Friday I see that it is so. Those (old) diagnostics indicate you have plenty of room on cache for these next operations. If that is not still the case post another diagnostic and we can work something else out.

  1. Go to Settings - Docker and disable the docker service. Do the same for Settings - VM Manager if you use that.
  2. Go to Main - Array Operation, click Move Now and wait for it to complete.
  3. Go to Shares - User Shares and click on Compute All. Wait for the results.

After all that, ideally the appdata and system shares should exist only on cache, and all other shares should not have any contents still on cache.

 

If everything looks good re-enable dockers (and VMs if used).

If not then come back and we will see what needs additional attention to detail.

 

6

1. which results i should see?

i can delete the appdata share, right now i have only 2 application. 

2. by saying "ideally the appdata and system shares should exist only on cache" means that when i create Appdata share - in the setting "Include disks" - need to be empty? how i make it exist only on the cache? by "Use cache disk - only" ?

3. i dont have System share 🤔maybe its because the os installed on Disk on Key? 

4. in the Shares Tab, in User Shares : appdata and Download, and in  DIsk Shares: cache, its indicate that "Some or all files are on unprotected storage" with the orange warning sign. what can i do?

 

Thank you all for the patience, i really appreciate your help

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Did you actually carry out the steps I outlined? You don't say.

 

Looking again at your diagnostics, I see you actually have your docker image in appdata, so you don't have a system share. That is OK.

 

You should clear the include on the appdata share. It is already cache-prefer, which is what allows it to be moved to cache. If some of it is not on cache then leave it cache-prefer.

 

Unless you have a cache pool, any files on cache are not protected. That is normal. You really shouldn't be sharing your disks in my opinion. If you turn that off then you won't show anything under Disk Shares.

 

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