How to uninstall NSM
If you would like to remove NSM(Network & Security Manager) related software packages and disk files to do a fresh install, the following command does this;
rpm -qa | grep netscreen | xargs rpm -e ; rm -rf /usr/netscreen/* /var/netscreen/*
It removes rpm packages containing “netscreen” and then deletes everything under default installation directories /usr/netscreen/ /var/netscreen