To me it sounds like you have the normal esxi 5.1 problem that changes aren't saved after a reboot. I've heard there are fixes for this using scriots to write back config lines into root and local.sh but I've never done these myself.
Maybe you've got a collegue or something that has made a script that writes back the only line you see after reboot? And to solve the problem all you need to do is add the rest?
I don't know, just a hunch. Here's the authors writeup on the reboot problem;
http://www.virtuallyghetto.com/2011/08/how-to-persist-configuration-changes-in.html?m=1
/Daniel
27 jun 2013 kl. 12:36 skrev "Giuseppe74" <communities-emailer@vmware.com<mailto:communities-emailer@vmware.com>>:
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