Re: ZFS is the right choice for a server system
This is wrong. DIF/DIX disks does not protect against data corruption sufficiently. Have you ever looked at the specs for disks with DIX/DIF? All enterprise hard disk specs say something like "1 irrecoverable error on every 10^17 read bits", fibre channel, sas, etc - all equipped with DIX/DIF. The moral is that those disks also encounter corruption and when that occurs - they can not repair it. Also, these disks are susceptible to SILENT corruption - corruption that the disks never noticed. That is the worst corruption.
ZFS detects all forms of corruption and repairs them automatically if you have redundancy (mirror, raid, etc). DIF/DIX disks can not do that. Even if you have a single disk with ZFS, you can provide redundancy by using "copies=2" which makes all data duplicated all over the disk, halving disk storage.
"...ZFS is based around RAID5/6, which is frankly does not scale..."
This is pure wrong. A hardware raid card can only manage a few disks, so hw raid cards does not scale. OTOH, ZFS utilizes the disks directly, which means you can connect many SAS expanders and JBOD cards, so a single ZFS server can manage 1,000s of disks or more - you are limited by the number of ports on the server motherboard. ZFS scales well because it can use all the JBOD cards. A single hw raid card can not connect to all other hw raid cards - hw raid does not scale. ZFS scales.
In fact, the IBM Sequioa supercomputer has a Lustre system that uses a ZFS pool with 55 Petabyte data and 1TB/sec bandwidth - can a hardware raid card handle a single Petabyte? Or sustain 1TB/sec? Fact is, a CPU is much faster than a hw raid. So a server with TB of ram and 100s of cores, will always outclass a hwraid card - how can you say that ZFS does not scale? It uses all the resources of the entire server.
Regarding high RAM requirements, if you google a bit, there are several people running ZFS on raspberry pie with 256MB RAM. How can that be?
Also, you can change OS and servers without problems with ZFS. Change disks to another server, change OS between Solaris, Linux, FreeBSD and MacOS. You are free to choose
ZFS is the safest filesystem out there, scales best and is most open. Read the ZFS article on wikipedia for research papers where the scientists compare ZFS against other solutions, such as hw-raid and conclude that ZFS is the safest system out there. CERN has released several research papers saying the same thing - read the wikipedia article on ZFS.