In addition to what the others have said:

For NetStorage, you can do:

/etc/init.d/novell-xsrvd stop

However, both NetStorage and iMan use tomcat and apache as well.

If all you want to do is restart things (sometimes required when you
update iManager), you can usually just restart tomcat.

rcnovell-tomcat5 restart

The opinions expressed are my own.
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