If one live-installs IRIX 6.5.21 on an Octane without applying patch 5086, it will kill the PROM, rendering you unable to boot the Octane anymore! Check out this forum thread.
Be absolutely sure that you have patch 5086 installed on your Octane, if you want to upgrade to 6.5.21. The patch is previously explained in this forum thread.
A miniroot 6.5.21 install should be fine, provided you boot the miniroot from the 6.5.21 install CD.


I made a live upgrade of my 2x300MHz R12k Octane
from 6.5.20f to 6.5.21f and it worked fine. I
didn't install this patch before.
/Muller
Correct. Irix 6.5.20 already has the newer versions of the inst/swmgr programs included so it doesn't need the patch