It’s not the next day, but I spent some time messing with mdadm and setting up RAID on Linux. Fairly easy process. I have neither the hardware nor use for setting up something for real, so I haven’t really seen what it can do as far as performance and just how long it takes to resync after growing, etc.
To mess with this I cobbled together a couple bash scripts, one does various array builds, RAID level upgrades, and resizes, the other tears everything down so I can start again.
You can find the build script here (safe_raid.sh) and tear down here (unraid.sh). To run you need to call them as root, since they involve file systems. Also, be aware that RAID is picky about things (as it should be), so jumping right through safe_raid will not give you a working RAID volume, you have to wait for some processes to complete before moving on.
