password protection

Dear support,
I'd like to control the access to my datasets (thredds version 3.8.03). I tried to configure Tomcat Users. Now all seems to works but I can't get ascii data (after the authentication). I can see an empty web page and and I can read this error in catalina.out:

OUCH! IOException: Server returned HTTP response code: 401 for URL: http://137.204.52.160:8080/thredds/dodsC/agg/climatology.dods
java.io.IOException: Server returned HTTP response code: 401 for URL: http://137.204.52.160:8080/thredds/dodsC/agg/climatology.dods
        at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:800)
        at dods.dap.DConnect.openConnection(DConnect.java:193)
        at dods.dap.DConnect.getDataFromUrl(DConnect.java:451)
        at dods.dap.DConnect.getData(DConnect.java:410)
        at dods.servlet.dodsASCII.sendASCII(dodsASCII.java:92)
        at dods.servlet.DODSServlet.doGetASC(DODSServlet.java:862)
        at dods.servlet.DODSServlet.doGet(DODSServlet.java:1459)
        at dods.servers.netcdf.NcDODSServlet.doGet(NcDODSServlet.java:264)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:237)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:214)
        at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
        at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:198)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:152)
        at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:540)
        at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:102)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137)
        at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:118)
        at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:102)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
        at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
        at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
        at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
        at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:799)
        at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:705)
        at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:577)
        at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:683)
        at java.lang.Thread.run(Thread.java:534)

In my ${tomcat_home}/webapps/thredds/WEB-INF/web.xml I added this security-constraint:
 <security-constraint>
    <display-name>User thredds</display-name>
    <web-resource-collection>
      <web-resource-name>thredds allowed</web-resource-name>
      <url-pattern>/dodsC/*</url-pattern>
      <http-method>GET</http-method>
    </web-resource-collection>
    <auth-constraint>
      <role-name>thredds</role-name>
    </auth-constraint>
    <user-data-constraint>
      <transport-guarantee>NONE</transport-guarantee>
    </user-data-constraint>
  </security-constraint>

I'd like to know how to limit data access.

Best regards, Luca

--
Giacomelli Luca
Laboratorio di Simulazioni Numeriche del Clima e degli Ecosistemi Marini
Università degli Studi di Bologna-Corso di Laurea in Scienze Ambientali
Via S.Alberto 163, 48100 Ravenna
Tel. +39 0544937324 - Fax +39 0544937323

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