What is the correct way to move data from one cache to another?


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I'll give it a try tonight and hopefully dont mess this up.

Is the data of shares, where I did choose "yes" for the caching option also present on the disk array, once move did his job? Or will there be data left on the cache? My understanding is, that only "Prefer & Only" keep data on the cash beyond a mover run.

I still struggle to understand the flow of data between cache and the array.

 

With the increasing usage of SSDs I think this could be a feature ("Cache Migrator") that would be usefull for a lot of users.

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13 minutes ago, doesntaffect said:

I still struggle to understand the flow of data between cache and the array.

It should be clear if you turn on the GUI help, first set those shares to cache="yes", disable docker service (also VM if applicable), run the mover, when done set the shares to cache="prefer" and select the new cache pool, run the mover again.

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1 hour ago, doesntaffect said:

Or will there be data left on the cache?

If you neglect to stop the services, mover won't touch open files, so you could end up with remnants. Safest way is to disable the docker and vm services when you are doing massive reconfigurations like that.

 

Also, on the shares page, the compute buttons will show you how the data is distributed across your devices so you can make good decisions on what settings to change to get things moved where you want.

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  • 5 months later...

I'm trying to do basically the same thing (move a share from one cache pool to another) so I thought I'd try this thread rather than starting a new one. I have tried the suggestions above:

  1. Change share from 'prefer cache' to 'yes'
  2. Disable docker and VMs in settings
  3. Trigger mover
  4. Change share back to 'prefer cache' with the new cache
  5. Trigger mover
  6. Re-enable docker and VMs

However, my share is left unchanged with all of the files remaining on the old cache - they never even get moved to the array. I'm not aware of anything holding the files open. What could be going wrong?

 

Thanks!

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Thanks for the response. I'm getting a ton of:

May 30 09:36:21 Bunker move: move: file <filename>
May 30 09:36:21 Bunker move: move_object: <filename> File exists

 

And it's actually happening for other shares that I wasn't trying to relocate to the other cache.

 

Strangely, when I look at the disks directly (on the array) I don't see all of the files that it is referring to. I see other threads where the suggestion is to delete the files on the array and trigger mover again, but in this case I don't see the files to delete them. In most cases, I don't see the conflict.

 

Another note (probably just an unrelated bug): the GUI displays the wrong cache name (I changed the name of the primary cache) on the Shares tab.

 

 

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  • 1 year later...
  • 1 year later...
On 8/1/2022 at 2:15 PM, JorgeB said:

Yes, if the existing cache is using btrfs.

Just had the same issue.  Cannot get most files to move on appdata from cache A to cache B.  I set appdata to array then I stopped all of the dockers individually.  When I run mover all I get is the following:

 

Aug 15 20:05:37 Odin emhttpd: shcmd (194): /usr/local/sbin/mover |& logger -t move &

Aug 15 20:05:37 Odin move: mover: started

Aug 15 20:05:37 Odin move: skip: /mnt/cache_default/isos/virtio-win-0.1.221-1.iso

Aug 15 20:05:37 Odin move: file: /mnt/cache_default/isos/.DS_Store

Aug 15 20:05:37 Odin move: move_object: /mnt/cache_default/isos/.DS_Store File exists

Aug 15 20:05:37 Odin move: skip: /mnt/cache_default/isos/Win10_21H2_English_x64.iso

Aug 15 20:05:37 Odin move: mover: finished

 

No mention of appdata files moving.  Tried it several times and Mover does not move anything.

 

Both of my caches are XFS, which if I understand the last comment, means they won't migrate automatically?  What do I need to do to move these files?  Thanks.

 

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8 hours ago, The Transplant said:

Just had the same issue.  Cannot get most files to move on appdata from cache A to cache B.  I set appdata to array then I stopped all of the dockers individually.  When I run mover all I get is the following:

 

Aug 15 20:05:37 Odin emhttpd: shcmd (194): /usr/local/sbin/mover |& logger -t move &

Aug 15 20:05:37 Odin move: mover: started

Aug 15 20:05:37 Odin move: skip: /mnt/cache_default/isos/virtio-win-0.1.221-1.iso

Aug 15 20:05:37 Odin move: file: /mnt/cache_default/isos/.DS_Store

Aug 15 20:05:37 Odin move: move_object: /mnt/cache_default/isos/.DS_Store File exists

Aug 15 20:05:37 Odin move: skip: /mnt/cache_default/isos/Win10_21H2_English_x64.iso

Aug 15 20:05:37 Odin move: mover: finished

 

No mention of appdata files moving.  Tried it several times and Mover does not move anything.

 

Both of my caches are XFS, which if I understand the last comment, means they won't migrate automatically?  What do I need to do to move these files?  Thanks.

 

 

You set things up wrong :)     If you are using a 6.12.x release then you set up the array as secondary storage and mover direction as cache->array.

If using an earlier release then you set Use Cache=Yes.

 

In both cases you stop the docker and VM services under Settings and then run mover to get files moved to the main array.

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