Error when starting WSO2 servers after changing default ports

Error

The followign error might occur when starting WSO2 servers after changin there default ports.

ERROR

{org.apache.coyote.AbstractProtocol} - Failed to start end point associated with ProtocolHandler ["http-nio-80"] {org.apache.coyote.AbstractProtocol}

java.net.SocketException: Permission denied
at sun.nio.ch.Net.bind0(Native Method)
at sun.nio.ch.Net.bind(Net.java:444)
at sun.nio.ch.Net.bind(Net.java:436)
at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:214)
at sun.nio.ch.ServerSocketAdaptor.bind(ServerSocketAdaptor.java:74)
at org.apache.tomcat.util.net.NioEndpoint.bind(NioEndpoint.java:470)
at org.apache.tomcat.util.net.AbstractEndpoint.start(AbstractEndpoint.java:617)
at org.apache.coyote.AbstractProtocol.start(AbstractProtocol.java:444)
at org.apache.catalina.connector.Connector.startInternal(Connector.java:1010)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.wso2.carbon.tomcat.internal.CarbonTomcat.startConnectors(CarbonTomcat.java:379)
at org.wso2.carbon.tomcat.ext.transport.ServletTransportManager.startTransports(ServletTransportManager.java:79)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

Possible Reason and Solution

You are getting this permission denied exception because the user you are running the instance does not have sufficient privileges (root permissions). All the ports below 1024 are called Privileged Ports and in Linux. Hence they are not allowed to be opened by any non-root user. It is a unix system security feature which prevents malicious users from setting up a malicious service on a well-known service port. To fix this you need to run the wso2carbon server as a root user. But before proceeding  make sure that you have setup the java environment ( setup PATH and JAVA_HOME environmental variables correctly) for the root user.