How to prevent auto shutdown after the OS is installing using jumpstart ?

Setting diag-switch to true drops the system into the OBP instead of booting, so the next step is for it to boot,
which pretty much means that the system rebooted, it just took longer. I suspect that what the original poster wants
is not to prevent the boot up, but to rather prevent the shutdown, presumably to do some post install configuration/logging. Again, your best bet is to do it in the finish script.

Sorry, but I don't agree with you. The 25K domains doesn't go to the obp, but remains on the # prompt created by the jet.  

Thank you :-)