External LDAP JNDI connectivity using Tomcat

问题:

I wanted to Know how external LDAP is connected using JNDI configuration in TOMCAT.

My code is something like

try {
    InitialContext iniCtx = new InitialContext();
    ctx = (LdapContext) iniCtx.lookup("external/ldap/worker");
    //System.out.println("LDAP Context initialized::"+ctx);
    if(ctx!=null) {
        urlProvider=ctx.getEnvironment().get("java.naming.provider.url").toString();
    } 

} catch (NamingException ne) {                        
    throw new NamingException(ne.toString());
} 

My Context.xml in Tomcat has following entry

<Resource 
  useDataSourceFactory="true"
  name="external/ldap/worker"
  auth="Container"
  type="com.sun.jndi.ldap.LdapCtxFactory"
  java.naming.factory.initial="com.sun.jndi.ldap.LdapCtxFactory"
  java.naming.provider.url="ldap://corpt605.corporate.***.***:13891"
  java.naming.security.authentication="simple"
  java.naming.security.principal="uid=cpasysuser,ou=******,o=***.com"
  java.naming.security.credentials="*********"
/>

And my web.xml has following entry

<resource-ref>
    <description>E2k Ldap Datasource example</description>
    <res-ref-name>external/ldap/worker</res-ref-name>
    <res-type>com.sun.jndi.ldap.LdapCtxFactory</res-type>
    <res-auth>Container</res-auth>
</resource-ref>

When I use this JNDI datasource I get following error:

08 Oct 2014 10:12:03,394 ERROR waveset.ge.commons.LdapJndiConnection_CDI:52 - getLdapCntxt::Error occured during Ldap context lookupjavax.naming.NameNotFoundException: Name [external/ldap/worker] is not bound in this Context. Unable to find [external].

What is wrong?