How to disable Xserve power saving while running ESXi

This isn't an answer as such but a fudge/hack that stops the timeout issue by writing regular random data to each drive (static data doesn't appear to work).

Create a shell script as below (mine is called .bmreadloop) on VMFS attached boot storage:

#!/bin/sh

while [ 1 -lt 2 ]
do

</dev/urandom sed 's/[^[:digit:]]\+//g' | head -c10 > /vmfs/volumes/bonoboBoot/.blah

</dev/urandom sed 's/[^[:digit:]]\+//g' | head -c10 > /vmfs/volumes/bonoboTwo/.blah

</dev/urandom sed 's/[^[:digit:]]\+//g' | head -c10 > /vmfs/volumes/bonoboHDD/.blah

</dev/urandom sed 's/[^[:digit:]]\+//g' | head -c10 > /vmfs/volumes/bonoboThree/.blah

sleep 10

done

Add run it on startup in /etc/rc.local.d/local.sh:

/vmfs/volumes/bonoboBoot/.bmreadloop >> /dev/null &

It's ugly but it works!