Install nxserver
yum install nx freenx
cd /etc/nxserver
cp node.conf.sample node.conf
vi node.conf
Ensure that this line is not commented out:
ENABLE_PASSDB_AUTHENTICATION="1"
Setup NX Server
vi /etc/ssh/sshd_config
nxserver --adduser craig
nxserver --passwd craig
touch /var/lib/nxserver/home/.ssh/known_hosts
cd /var/lib/nxserver/home/.ssh/
chown nx:root known_hosts
vi /etc/nxserver/node.conf
Install NX client
Depends on your operating system, in my case it was windows https://www.nomachine.com/download
Setup Client
Grab DSA key from here that you will need for the client
vi /etc/nxserver/client.id_dsa.key
Sources: http://wiki.centos.org/HowTos/FreeNX
centos nomachine gnome kde