With the secondary distributions installed, the steps to use
them are:
It is important to use a 2.4-series or newer Linux kernel in the
"primary" Linux distribution in order to take advantage of the
multiple mount points feature that the 2.4-series permits. For many
tasks, the /proc filesystem will have to be
remounted in the secondary distribution using:
mount --bind /proc /opt/distros/redhat_6.2/proc
Also, it can be helpful to remount (rather than copy) the source tree
from the primary to the secondary distro:
mount --bind /home/USER/src/PROJECT /opt/distros/redhat_6.2/USER/src/PROJECT
Become root and use:
chroot /opt/distros/redhat_6.2 /bin/bash
to obtain a shell with one of the secondary distros.
Finally, create a user (if necessary) within the
chroot-ed shell and develop, build, and/or test
your application within this "separate" Linux distribution!
Done! You now have a shell that is, for all practical
purposes, running within the secondary Linux distribution of your
choice.