After you have installed your system, you will no doubt want to update your ports tree regularly.
To do this, edit/create a file called /root/bsdports which contains the following:
*default tag=.
*default host=cvsup2.us.freebsd.org
*default prefix=/usr
*default release=cvs delete use-rel-suffix compressports-all
You should change the host “cvsup2.us.freebsd.org” to be one of your local mirrors. You can see a list of mirrors at http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/cvsup.html#CVSUP-MIRRORS
Now to update your ports tree, type:
csup /root/bsdports
This takes quite a while, and will report any files it is updating as it goes. Once it completes, your ports tree will be up to date.