Remove HDD from Parity Array

[TheFloyd]

Struggling to find my exact scenario.   I made the mistake of adding my security camera HDD to my main drive array.   At the time i was new to unraid and didnt realise that even though i had a specific spec drive for my cameras, my parity drive would be busy writing all the changes too.   The reality is, that couldnt care less about my security footage if the drive failed, so i would rather take the load off the array and jsut have it as a stand alone drive on the unraid server.   if you google this scenario, all you find is people shrinking their array and others wanting to remove their parity drive.   what i want to do is pull my purple surveillance drive out of my main array and add it as a single drive with no redundancy, then point my existing security camera unraid share to it, in its new location.  surely someone has a procedure for this?   for such low value, write-heavy load, i want it to be stand-alone and free up the performance of my main array with parity for all of everything else.

[Squid]

What you would want to do is go to Tools - New Config (keep all assignments)

 

Then from Main unassign the security drive and then re-assign it to a new Cache Pool

 

You will need to re-build parity (it is no longer valid)

[TheFloyd]

Thanks Squid, for the unbelievably quick response.   I must admit my degree of terror when reading the simplicity of your solution   my main array underpins many TB of storage from many VM's and docker containers etc.    following your steps, would the existing share that points specifically to this physical disk in the array, follow it, or would i need to create a new share to it and update any and all references to it?    I presume that following this, my parity disk will thrash like hell for a day or so while it rebuilds etc.

[Squid]

You would have to adjust the share settings to point specifically to that new cache pool, and (presumably) set the Use cache settings to be only.

[TheFloyd]

Thanks Squid, but i am worried that i am using the wrong terms here, or that i am still a bit of a noob....    you are talking about 'cache pools' and in my mind this is talking about the SSD's that i have as cache drives in the system that i use for some shares and specifically for my VM's etc.    the drive i want to pull is a super slow WD purple spinning disk that has no cache drive associated with its share.   it just has 8 security cameras bludgeoning it with footage 24/7, and i wanted to take that heat off my parity drive.   i was following you with the first suggestion 'new config', but i got confused when you started talking about new cache pools.    i was somewhat expecting that i would need to remove the purple HDD, tell the array to forget it and rebuild the parity, then  create a new drive array with a single purple drive in it and no parity, then use magic to move the existing share over to this physical disk.     using the term 'cache' threw me a little as it means something different to me.    where did i go wrong?

[Squid]

Anything outside of the array is a "Cache Pool".  Previously you would accomplish something like what you want via mounting the drive in Unassigned Devices.  But, it's easier to let the OS itself manage it as a cache pool.

 

No physical disconnecting is required.  You're just rearranging how the system thinks the drives are assigned.

 

Your new config allows you to remove the drive from the array (parity will need to be rebuilt).  And you hit add pool to add another cache pool that is specific to the security drive.

 

Writes etc to that drive won't involve parity at all, and you can still access it via the user shares, so no adjustment to any VM's or Docker containers is required.  Just the shares that exist on that drive you set to be "Cache Only" and to use that new cache pool.

[TheFloyd]

Hi Squid, 10 out of 10 for being super helpful !   thanks a bunch, i will give this a shot!