Hi

 

I'm slowly setting up my unRAID server which I'm gradually getting there. I have a couple drives in the normal array and I also had a m2 250GB drive for cache. My new m2 1TB drive arrived today which I want to use for cache, so I followed a video on how to swap drives, and started working on it. In the end though, I decided that I might as well also use the 250GB drive for the cache coz I already have it, so I should then have 1.25TB of cache. Well, I must have stuff up somewhere coz that's not what has happened. 

 

As the server is new, did a new config. I've tried putting the drive in various positions and have run what I thought was a format many times, but the system always thinks it's in a pool and subsequently shows it as a much smaller device in the way of available space. 

 

I was just thinking that I could boot into a disk utility and format the drive, but I'm concerned that it won't change a thing. 

 

Sorry for the long story above. If anyone has any ideas to share, I'm all ears! Thanks

 

The default for a pool is RAID1 (for redundancy), so with 2 drives of different sizes the available space is that of the smaller drive.

 

if you want to have all the space available (rather than having redundancy), then click on the pool on the Main tab and change it use the ‘Single’ profile and then initiate a Balance..

Thank you for your reply. 

 

I've ended up sorting out a fix. I've done heaps of searching and I found some posts which said what you said, others that said that it will say that it has the smaller amount available but that I could ignore it, others that said it would always go by the amount available on the smallest drive which would just be doubled, and other posts in the middle. So to be certain I end up with something decent in the way of space, I just removed the smaller drive, did lots of different formats on the drive, and I now have 1TB as my cache. It's a result I can live with

If you have the physical space and want to continue using the 250, simply add a new pool on the main GUI with the array stopped, assign the 250 to it, name the pool, and use it for whatever fits. You will probably need to run the blkdiscard command on the raw device ID of the 250 to allow it to be formatted correctly since it was previously part of a BTRFS RAID set, and Unraid doesn't properly remove that info sometimes, but adding it as a second pool would be my first choice rather than trying to join the 250 and 1TB as you originally attempted.