This creates a successful NFS host in CentOS. Guides from https://www.digitalocean.com/community/tutorials/how-to-set-up-an-nfs-mount-on-centos-6 and http://www.unixmen.com/nfs-server-installation-and-configuration-in-centos-6-3-rhel-6-3-and-scientific-linux-6-3/

CentOS 6 nfs creation steps

yum install nfs-utils
chkconfig nfs on
service rpcbind start
service nfs start
vi /etc/sysconfig/iptables # (see iptables edit for changes to make)
service iptables restart
# Add entires to /etc/exports
exportfs -a(v)

iptables edit

# this goes in /etc/sysconfig/iptables
# after the *filter line (not sure if it matters, but it works there!)
-A INPUT -m state --state NEW -m tcp -p tcp --dport 2049 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 111 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 32803 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 892 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 875 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 662 -j ACCEPT