Installing packages from BSD Installer CD's

I'm looking at ways to install packages with the BSD Installer.

One way is to move the few executables and libraries needed from /usr to another location on /dev/md0. These include /usr/bin/login, /usr/sbin/bsd_installer_be, /usr/sbin/bsd_installer_ncurses, /usr/lib/libaura.so, /usr/lib/libdfui.so and /usr/lib/libinstaller.so but there may be others. /usr would then be unmounted and the package CD gets mounted in it's place. When all the packages are installed it would be unmounted and the install CD mounted back to /usr.

Another is to move /usr to a file system image. The dists would stay directly on the CD but it could be unmounted as needed without any problems.

The only problems I see with the former is I don't know if any further files from /usr will be needed in the future. The latter will need more memory which I'm trying to keep to a minimum as swap is not available until part way through the install.

I have only started testing to see if I can unmount /usr, remove the physical CD and still access / with it.

If anyone has any other ideas on how to change the CD during the install please leave a comment.