I have hard time to decide that which filesystem is the best and Raid or not Raid selection. I have 4 different hard disk. 1. 120GB SSD 2. 160GB 3. 500GB 4. 1TB
And I have noticed that zfs on linux does not support trim officially but third party patch, therefore, it is not fully tested....
As a result, I don't intend to let my ssd use zfs, I will use ext4 instead...
So, Is zfs on linux reliable enough to be installed with gentoo on a network attached storage? Or you guys have another good solution for me? P.S. if zfs is reliable enough, RAIDZ is a good choice?
In your description you mention a set of disks you want to use. If you would use this set in e.g. RAIDZ and one disk crashes, your disk-array would lose all its data.
Reliability is a very broad expression;
If you want to protect your data agains bit-rot, then ZFS is an excellent choice.
If you would use it with your available disks and you would like to protect your data against hardware failures, consider using a more homogene set of disk.
Regarding your selection of OS, try OpenIndiana http://openindiana.org/ or some turn-key OS like http://www.freenas.org/ for relatively simple (but effective) configurations.