# mkdir /foo ; mount c0t0d0s6 /foo # cd /var ; tar cf - . ; (cd /foo ; tar xfBp - ) # umount /foo # mv /var /xvar # mkdir /var # mount c0t0d0s6 /varYou can move /opt similarly. But note that you CANNOT move /usr this way on a running machine... it's like trying to saw off a tree branch while you're sitting on it. You must boot from CD to do that.
If a search engine dropped you directly into this document, you should go to the index page to find out what you're reading. This document is a record of a project from 1999-2000 -- it is not a current guide to installing any software product.