How to change the port of Tomcat from 8080 to 80?

Ubuntu 14.04 LTS, in Amazon EC2. The following steps resolved this issue for me:

1. Edit server.xml and change port="8080" to "80"

sudo vi /var/lib/tomcat7/conf/server.xml

<Connector connectionTimeout="20000" port="8080" protocol="HTTP/1.1" redirectPort="8443"/>

2. Edit tomcat7 file (if the file is not created then you need to create it)

sudo vi /etc/default/tomcat7

uncomment and change #AUTHBIND=no to yes

3. Install authbind

sudo apt-get install authbind

4. Run the following commands to provide tomcat7 read+execute on port 80.

sudo touch /etc/authbind/byport/80
sudo chmod 500 /etc/authbind/byport/80
sudo chown tomcat7 /etc/authbind/byport/80

5. Restart tomcat:

sudo /etc/init.d/tomcat7 restart

On a Linux Debian-based (so Ubuntu included) you have also to go to /etc/default/tomcat7, uncomment the #AUTHBIND=no line and set its value to 'yes', in order to let the server bind on a privileged port.

1) Go to conf folder in tomcat installation directory

 e.g. C:\Tomcat 6.0\conf\

2) Edit following tag in server.xml file

<Connector connectionTimeout="20000" port="8080" protocol="HTTP/1.1" redirectPort="8443"/>

3) Change the port=8080 value to port=80

4) Save file.

5) Stop your Tomcat and restart it.