Move VMs to cache

[Fifthy]

Hi!

I made a crucial mistake during my setup, i only have one disk (ssd) in the server which i added as Disk 1 and that houses my VMs. I have another ssd laying around and i thought i'd make a cachepool and add my vm share to that instead.

So how do i do this without having to reinstall everything?

Is it possible to add a hdd to the array and move the VMs to that drive and then wipe the original disk 1 ssd and create a ssd cache with the other ssd i have laying around and move the VMs back to the cachepool?

Or is it just easier to backup the VMs and reinstall everything?

[itimpi]

You have to have at least one drive in the array.   Do you have a drive you can use for that purpose? 
 

if you do then you could do the following basic process:

• Add the second SSD as a Cache device formatted to BTRFS
• move the VM to the new cache drive
• do a New Config and create a new array without the first SSD but including the drive to be used as the array device
• add the first SSD to the second one already in the cache to create a cache pool.

[Fifthy]

12 minutes ago, itimpi said:

You have to have at least one drive in the array.   Do you have a drive you can use for that purpose? 
 

if you do then you could do the following basic process:

• Add the second SSD as a Cache device formatted to BTRFS
• move the VM to the new cache drive
• do a New Config and create a new array without the first SSD but including the drive to be used as the array device
• add the first SSD to the second one already in the cache to create a cache pool.

Yes i have a 3tb laying around thats practicly brand new.

 

That was basicly my ide also but how do i do a "new config and a new array" ?

[itimpi]

1 minute ago, Fifthy said:

how do i do a "new config and a new array" ?

New Config is an option on the Tools tab of the Unraid GUI.

[Fifthy]

1 hour ago, itimpi said:

New Config is an option on the Tools tab of the Unraid GUI.

and by "move the vm" you mean changing all shares (appdata,domain,isos, system) to "cache only" and no "included drives"

[itimpi]

Just now, Fifthy said:

and by "move the vm" you mean changing all shares (appdata,domain,isos, system) to "cache only" and no "included drives"

No.    Change them to Use Cache = “Prefer”; disable the Docker and VM services;  and then run mover to get files moved to cache.   Included drives then becomes irrelevant if the files are not on the array.    Once the files are on the cache you can (optionally) change them to Use Cache = Only if you want.

[Fifthy]

4 minutes ago, itimpi said:

No.    Change them to Use Cache = “Prefer”; disable the Docker and VM services;  and then run mover to get files moved to cache.   Included drives then becomes irrelevant if the files are not on the array.    Once the files are on the cache you can (optionally) change them to Use Cache = Only if you want.

Doing a preclear on the hdd now, then hopefully  thanks!

[HackHome]

On 1/3/2020 at 10:52 PM, itimpi said:

No.    Change them to Use Cache = “Prefer”; disable the Docker and VM services;  and then run mover to get files moved to cache.   Included drives then becomes irrelevant if the files are not on the array.    Once the files are on the cache you can (optionally) change them to Use Cache = Only if you want.

How to "run mover"?

[ChatNoir]

3 minutes ago, HackHome said:

How to "run mover"?

There is a 'Move' button at the bottom of the 'Main' page.

[HackHome]

On 10/14/2022 at 10:59 PM, ChatNoir said:

There is a 'Move' button at the bottom of the 'Main' page.

Ah thank you. A faster way than just the "Use cache" setting to "Prefer" (in Share => Settings). Thank you!
With that setting one more question: What happens if my SSD Cache drive fails now. Will all files be lost or does Unraid keep a copy of these files also on array?

[JonathanM]

5 hours ago, HackHome said:

What happens if my SSD Cache drive fails now. Will all files be lost or does Unraid keep a copy of these files also on array?

By design files only exist in one location, either the array or one of the pools.

 

If your pool is configured with multiple drives in a healthy fault tolerant configuration like RAID1, then a device failure should be covered.

 

In any case, pool or parity array, important files must be backed up elsewhere. RAID or Unraid is not a substitute for backups, it can't help with file corruption or deletion, only disk failure.

 

In my opinion for VM's you should be using the same strategy you would use for a regular desktop, where you have a backup client on the OS itself, be it windows backup, acronis, or whatever.

[HackHome]

okay, thanks