Storage server configuration?

Question

Backup

Essence of the question: it is
necessary to assemble the optimal configuration of servers for data storage. From 40 to 100 discs.
What is better now than 2 RAID adapters or JBOD with a software implementation of RAID or another means of creating a fault-tolerant array?
Load: backup, linear multi-threaded recording.
What amount of RAM will be optimal? Need an SSD?
Which way is better to look?

Answer 1

Which way is better to look?

In the direction of contacting the integrator. This is a serious job, and you want it done here for free :)

Answer 2

Based on the fact that the disks write 100mb / s
If the zfs system file - you need a cache on the ssd (any for 1tb of data - 1gb of RAM)
I'm behind raid 10 using mdadm