Is Postponing Cache Disk install a Problem?

[binar]

Fellow Forum Members,
Performing a Parity and hard drive initialization setup for the first time on my new UnRaid system is going to take 20 hours of waiting! For financial reasons I elected not to setup a pair of 2TB SSD cache disks at this time.

 

Is it very difficult to add cache disks at a future date after an UnRaid array is already completely setup with all hard drives assigned and formatted?  I am curious to know if it requires I wait another 20 hours for electing to postpone the addition of cache disks to a later time in the future?  Or do the cache disks operate outside of the UnRaid array which means no future 20 hour wait is necessary?

 

Lastly, for my future UnRaid Server Cache Disk setup I am considering to by an "M.2 To PCIe Adapter" like the ones shown in the links below:

 

https://www.sybausa.com/index.php?route=product/product&path=64_205&product_id=1035

 

https://www.newegg.com/asus-model-hyper-m-2-x16-card-v2-pci-express-to-4-x-m-2/p/N82E16815293043?Item=N82E16815293043&Description=m2 pcie ssd adapter&cm_re=m2_pcie_ssd_adapter-_-15-293-043-_-Product&quicklink=true

 

Is anybody in the UnRaid community using "M.2 To PCIe Adapter" as an UnRaid cache disk setup? Is this solution offer better results compared to using a pair of 2tb SSD hard drives? What I like about it is how I do not have to rely on using any of my motherboard SATA ports which I want to keep as spares.

 

Any opinions welcome. 

Edited May 25, 2020 by binar

[trurl]

43 minutes ago, binar said:

cache disks operate outside of the UnRaid array which means no future 20 hour wait is necessary?

^This

 

However, if you enable dockers/VMs before installing cache, then the shares related to dockers/VMs (appdata, domains, system) will get created on the array where your docker/VM performance will be affected by the slower array, and docker/VMs will keep array disks spinning. And it takes a few steps to get those shares moved to cache later.

[binar]

Thank you for the post Constructor.  I will avoid adding dockers until I first purchase the cache disks and install them onto my UnRaid server. Does anybody have any opinions on the "M.2 To PCIe Adapter" hardware I'm considering to use.  Does UnRaid support such "M.2 To PCIe Adapter" hardware for use as a cache disk?  Any opinions welcome.