Auto Start for Tomcat Service on Reboot
sudo chkconfig tomcat8 on
Adding an IP Rule to redirect 80 (http) to tomcat 8080 port
sudo iptables -A PREROUTING -t nat -i eth0 -p tcp –dport 80 -j REDIRECT –to-port 8080
To save iptable rules
sudo service iptables save
To add a user to a group
sudo usermod -a -G groupname username
To give read/write permission of a directory to members of group
sudo chmod -R g+w directory/