Tomcat Start Error java.net.BindException:Permission denied:80

When Tomcat starts, it reports the following error:

caused By:java.net.BindException:Permission denied <null>:80

At Org.apache.tomcat.util.net.JIoEndpoint.bind (jioendpoint.java:410)
At Org.apache.tomcat.util.net.AbstractEndpoint.init (abstractendpoint.java:640)
At Org.apache.coyote.AbstractProtocol.init (abstractprotocol.java:434)
At Org.apache.coyote.http11.AbstractHttp11JsseProtocol.init (abstracthttp11jsseprotocol.java:119)
At Org.apache.catalina.connector.Connector.initInternal (connector.java:978)
... More
Cause : Only the root user can access the port number below 1024 on the Linux system and the rest of the user cannot access it.

Workaround 1:

When you start Tomcat, use sudo./startup.sh or start with the root user

Workaround 2:

Modify Tomcat's server.xml configuration file,

Modify the port to 8081 (or the other port number above 1024, but not to the other ports on this computer),

Then use the root user to log on to the server and execute the Port redirection command:

Iptables-t nat-a prerouting-p tcp--dport 80-j REDIRECT--to-port 8081

(Redirect to port 8081 when you access port 80).

Tomcat Start Error java.net.BindException:Permission denied:80