New to unraid, some questions.

[doox00]

Hey all, I currently have a 2019 Server that is mostly used for my network share and some VMs atm, I have 6 4tb WD 2.5" ssd's in raid 5.  I backup weekly to an external USB 16tb hdd (just changed data).  I just built a new server and I want to move away from 2019 Server and use a hyper visor.  I am relatively new to Linux.  My 2019 server is a Ryzen 3950 with 64gb ECC unregistered Ram on a X570 motherboard and an LSI 9207-8i HBA (IT mode) that 6 the ssds are connected to and it is damn slow (the drive speed).  The server is connected with 2.5GB to the switch, my main pc in the house is 10g (rest of house/pcs are 1g) and the transfer speeds are decent to the 6 ssds for a few seconds and then stops transferring for a bit, then resumes and repeats, it is awful.  It was this way when I had just 1 gig network as well all over.  The new server is an Epyc 7302P cpu with 256gb ddr4 3200 ECC registered ram (8 32gb modules) on a Supermicro H12SSL-NT motherboard and will be 10g to the switch.   I would like the 6 ssds as the network share (with 1 parity drive) and used for VM's etc.  I have a new Exos 16tb drive I purchased to put in the new server to use as a backup drive.  I have a 1tb nvme drive to use as a cache drive in the server.  I am hoping this configuration will give me decent file transfer speeds (2-300+ MB/s without the pauses every few seconds).  

 

What file system should I be using and how should I setup the 6 ssd's (I want 1 parity drive so I can lose any drive and not lose data).  Will this configuration give me decent drive speeds? 

With the 16tb exos drive installed will I be able to do backups of only changed/new files daily, if so how do you recommend I do that? (I use robocopy on my win 2019 server)

When I remove the 6 drives from the current 2019 Server I will be doing a final backup to the usb 16tb hdd, will I be able to plug this drive in to the new server (NTFS FS) and copy over the files to the new share/array?  In order to do that will I have to share the usb drive and copy all the data "over the network" or is it possible to copy the data over in unraid (CLI)?
 

As far as the cache drive, is it recommended or even possible to use 2 of them and mirror them so in case one fails I don't lose data, is this necessary?  How long does the data stay on the cache drive before it gets moved to the array, does it do it immediately? 

 

If the cache drive were to fail (if not mirrored) you only lose the data that was on the cache drive, correct?  I can still boot up in unraid without the cache drive and have access to my data on the main array (6 ssd drives)?  I can then install a new nvme drive and tell unraid to use that instead as the cache drive?

 

Thanks for any guidance/suggestions!