<role rolename="manager"/>
<role rolename="manager-gui"/>
<role rolename="admin"/>
<user username="user" password="password" roles="admin,manager,manager-gui"/>

nano /etc/tomcat7/tomcat-users.xml

<role rolename="manager-gui"/>
<user username="tomcat" password="s3cret" roles="manager-gui"/>

sudo /bin/su - tomcat -c /usr/share/tomcat7/bin/shutdown.sh

ps aux | grep tomcat

sudo /bin/su - tomcat -c /usr/share/tomcat7/bin/startup.sh