software raid-0 array stops running when rebooted

using disk utility 2.30.1
-Formatted each of my 3 1.5 TB drives with a GUID partition table scheme.
-created 1 2 GB swap partition on each drive. (is this necessary? idk i was following a guide somewhere that said to create swap partitions)
-then going to file > create > RAID Array... i made my raid 0 stripe. with the remaining space on the 3 hard-drives.
- then mounted the drive proceeded to share it for my windows PC's to use.

i restart ubuntu

the Raid is stopped and not mounted anymore, sharing permissions gone when i manually mount it again after starting the raid.
i tried adding
"/dev/md0 /media/db ext4 rw,nosuid,nodev 0 0"

to my /etc/fstab/ file but that only made ubuntu angry because the raid is stopped and not started again when restarting.

i need to the raid to be always on... and always mounted and shared. what can i do?