starting tomcat on port 80 on CentOS release 5.5 (Final)

I want to start Tomcat 6.0.29 on port 80. My OS is CentOS release 5.5 (Final) I changed following line in $TOMCAT_HOME/conf/server.xml

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

<Connector connectionTimeout="20000" port="80" protocol="HTTP/1.1" redirectPort="8443"/>

Then I run command:

sudo /etc/init.d/tomcat6 start

In file $TOMCAT_HOME/logs/catalina.log I found such exceptions:

java.net.BindException: Permission denied <null>:80
    at org.apache.tomcat.util.net.JIoEndpoint.init(JIoEndpoint.java:549)
    at org.apache.tomcat.util.net.JIoEndpoint.start(JIoEndpoint.java:565)
    at org.apache.coyote.http11.Http11Protocol.start(Http11Protocol.java:203)
    at org.apache.catalina.connector.Connector.start(Connector.java:1087)
    at org.apache.catalina.core.StandardService.start(StandardService.java:534)
    at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
    at org.apache.catalina.startup.Catalina.start(Catalina.java:581)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
    at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
Caused by: java.net.BindException: Permission denied
    at java.net.PlainSocketImpl.socketBind(Native Method)
    at java.net.PlainSocketImpl.bind(PlainSocketImpl.java:365)
    at java.net.ServerSocket.bind(ServerSocket.java:319)
    at java.net.ServerSocket.<init>(ServerSocket.java:185)
    at java.net.ServerSocket.<init>(ServerSocket.java:141)
    at org.apache.tomcat.util.net.DefaultServerSocketFactory.createSocket(DefaultServerSocketFactory.java:50)
    at org.apache.tomcat.util.net.JIoEndpoint.init(JIoEndpoint.java:538)
    ... 12 more
0:11:56 org.apache.catalina.startup.Catalina start
SEVERE: Catalina.start:
LifecycleException:  service.getName(): "Catalina";  Protocol handler start failed: `java.net.BindException: Permission denied <null>:80
    at org.apache.catalina.connector.Connector.start(Connector.java:1094)
    at org.apache.catalina.core.StandardService.start(StandardService.java:534)
    at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
    at org.apache.catalina.startup.Catalina.start(Catalina.java:581)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
    at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
0:11:56 org.apache.catalina.startup.Catalina start`

Thanks in advance

Solution

The ports in the range 1-1023 are privileged. Only root is allowed to bind to them.

There is at least two ways to solve this:

Run as root. You need to weight the extra security risks this infers, of course; both security holes in Tomcat itself (which I believe to be few) and those your web applications contains (which can for example lead to letting people read /etc/shadow as an example), against this being simple and straight-forward.
Run as service with jsvc. See http://tomcat.apache.org/tomcat-5.5-doc/setup.html for details on jsvc. It is some extra hassle to setup, but root will only be involved in setting up the ports, Tomcat will then run as a user without special rights. I recommend this for any serious setup.

Regardless on what way you choose, the actual starting of Tomcat will need root privilegies.

///BR, JenEriC