[GLLUG] Software RAID advice

[Imran Chaudhry]

I'm setting up a new server which I'm going to be sysadmining on an
ad-hoc basis.

One requirement is RAID and looking into software RAID/mdadm leaves me
a little confused. All the examples I looked at put the system
directories (eg. / and /boot etc) on a non-RAID partition and the rest
/var /home on RAID.

I'm assuming I can use software RAID across entire devices right?

I'm aiming for between 2Tb and 4Tb of space. What RAID level would you
recommend for least noise/least amount of overall maintenance.

The server I'm looking at purchasing will be a second-user purchase -
some of these have hardware RAID built-in - I should always go with
hardware RAID over software right?

Lastly, does anyone has suggestions for servers which have low-noise?
This server will be running in a home office environment.

One I've seen available locally is FUJITSU Server PRIMERGY TX100 which
specifically mentions the low-noise aspect:
https://sp.ts.fujitsu.com/dmsp/publications/public/ds-py-tx100-s3.pdf

Thanks!