storage transfer question


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so.  my original set up was with 1tb platter HDD's making all my VM's run slow.  i have 1 per VM for a total of 3 VM's.  so 3x1tb + 1x2tb parity.  i recently picked up some 256gb SSD's.  moving forward, should i just remove 1 hdd with a SSD at  a time and will it let me resync?  or do i need to scrap the whole thing?  i believe i set the vdisk image size to the total size of the drive (1tb).  but as i look at the hdd usage, im noticing the vdisks arent taking up the whole disk.  Should i just scrap the whole thing and reconfig from scratch or will replacing 1 disk at a time work?

 

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The vdisk image files are sparse files. So disk will still show free space. But if you copy that file (depending on method) the copy will not be sparse. Copying a 1T sparse file to a 256G SSD won't work, and even if you found a trick to do it, would be highly discouraged. There are techniques to shrink/expand image file that you could use. Or starting over is always an option.

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im testing it now by creating a new test disk for one of the VM's and seeing if it reproduces the image successfully.  ill keep ya guys posted.  

 

Macrium uses a rescue disc that uses windows PE.  right now it has had my cpu's pegged for that VM for a while now.  not sure if it crashed or not.  yup it crashed.

 

More than one way to skin a cat.  created new Vdisk@256gb.  set it as a secondary hdd on my test VM.  im going try restore a macrium image to that secondary vdisk, and test booting it from my VM3.  

Edited by charleslam
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4 hours ago, charleslam said:

is there an easy way to clear the array information?

 

Not sure what you are asking. New config will clear your array configuration. Don't think that's what you want to do though.

 

One of the Spaceinvader One videos on YouTube explains how to shrink a vidisk file. Forget which one. Maybe @gridrunner can point you in the right direction.

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what i am trying to do is remove 3x1tb hdd and replace with 3x256gb ssd.  this will definitely cause problems with the array.  macrium reflect makes images of running partitions.  so i installed macrium on all 3 of my VM's and created image files of them.  saved on my server.  i am rebuilding one just to verify it will work after being shrunk.  so far i am at 36%.  once this has been verified (or i find that it destroys the image *shrugs*) i will move forward with replacing the hdd's with ssd's.  im not sure what unraid will do if i delete all hdd's and try to enable the ssd's.  id imagine it would say my array cannot be started due to the missing disks.  

 

trying to avoid doing the new config, but it might be the simplest.  

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to clarify, the shrinking occurs when the image gets loaded onto the new vdisk.  macrium makes images only of files it can see.  so for example on a bare metal install of my gaming pc.  i may have a 3tb drive, but it will only make an image of 1tb of data and can image a drive bigger than 1tb onward.  works well on traditional set ups.  does not work well on VM's apparently.  i know its something to do with fixing the mbr.  but my traditional tools on fixing this wont work it appears.  

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@charleslam  @SSD

 

Sorry just read this post. So you have an array with 1 parity and 3 data drives. You want to replace the data drives with ssds drives in the array, whilst keeping a parity disk.

This will work very poorly. You will still have to write to the parity drive on each write so it will be slow even with the ssds. Dont put the vms on the array. Have the ssds as unassigned devices then use them for the vms that way. That way reads and writes will be fast.

If you are worried about your harddrives failing so loosing a vm and thats why you want them on parity protected drives then just make backups of the vdisks to put on the array.

If you dont have enough sata ports for 3 ssds and the drives in the array you can either use a pcie sata card or if you dont store data on the array other than the vms then you can just use your largest drive in the array and have no parity, or just have one parity and one data.

 

 

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3 minutes ago, gridrunner said:

@charleslam  @SSD

 

Sorry just read this post. So you have an array with 1 parity and 3 data drives. You want to replace the data drives with ssds drives in the array, whilst keeping a parity disk.

This will work very poorly. You will still have to write to the parity drive on each write so it will be slow even with the ssds. Dont put the vms on the array. Have the ssds as unassigned devices then use them for the vms that way. That way reads and writes will be fast.

If you are worried about your harddrives failing so loosing a vm and thats why you want them on parity protected drives then just make backups of the vdisks to put on the array.

If you dont have enough sata ports for 3 ssds and the drives in the array you can either use a pcie sata card or if you dont store data on the array other than the vms then you can just use your largest drive in the array and have no parity, or just have one parity and one data.

 

Issue I was asking about was he appears to have a 1T vdisk on each of his spinners that would need to be reduced in size to fit on a 256G SSD. I remember one of your videos explained how to reorg the data and truncate the disk size, just don't remember which one.

 

I agree no parity on a disk holding VM images.

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3 minutes ago, SSD said:

 

Issue I was asking about was he appears to have a 1T vdisk on each of his spinners that would need to be reduced in size to fit on a 256G SSD. I remember one of your videos explained how to reorg the data and truncate the disk size, just don't remember which one.

 

I agree no parity on a disk holding VM images.

3

Yes, the OP could try this if there is enough free space in the vdisk.  However, try to make a backup of the vdisk first somewhere if possible as shrinking vdisks is always tricky.

Also, just a bit off topic don't try defragmenting thin provisioned disks as this can bloat them moving the blocks around.

Now it is possible to re-thin provision a vdisk too. I will make a video how soon. You need to use some tools called libguestfs (http://libguestfs.org/)  unfortunately they are not included in unraid. so what i have done in the past is to use them from a Linux VM such as fedora install the tools with  sudo yum install libguestfs-tools then using virt-sparsify you can reclaim the space  http://libguestfs.org/virt-sparsify.1.html 

 

 

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