noob questions

[ice545]

To my understanding, the FreeNAS OS must be installed on a standard alone volume such as
a small flash drive, SSD or spare HDD. But what happens when the OS drive crashes?
Can my data thats stored in the raidz array still be accessed if I re-install the OS back again?

 

[pirateghost]

From the DOCUMENTATION:

NOTE: if a previously working FreeNAS® system hangs after a FreeNAS® upgrade, check to see if there is a BIOS/BMC firmware upgrade available as that may fix the issue.
If the upgrade completely fails, don't panic. The data is still on your disks and you still have a copy of your saved configuration. You can always:
1. Perform a fresh installation.
2. Import your volumes in Storage → Import Volume.
3. Restore the configuration in System → Settings → Upload Config.

Same logic. Apply to a failed OS drive