Debugging mail sessions

When we debug a mail application, we can use the mail debugging feature. The mail component generates debugging information, on a per session basis, that can be used for problem determination or tuning. Enable the debug mode triggers the mail component of the application server to print the following data to the standard output stream:

• interactions with the mail servers
• properties of the mail session

This output stream is redirected to the SystemOut.log file for the specific application server.

Tasks

From the administrative console...

Resources > Mail > Mail sessions > mail session > Enable debug mode

Debugging is enabled for that session only.

Example

The following example shows sample mail debugging output:

ResourceMgrIm I   WSVR0049I: Binding Test as mail/test
SystemOut     O *** In SessionReferenceable.getReference:
SystemOut     O  added StringRefAddr: type=ws.transport.password, content=****
SystemOut     O  added StringRefAddr: type=ws.isolated.class.loader, content=false
SystemOut     O  added StringRefAddr: type=mail.transport.protocol, content=smtp
SystemOut     O  added StringRefAddr: type=mail.imaps.class, content=com.sun.mail.imap.IMAPSSLStore
SystemOut     O  added StringRefAddr: type=mail.smtp.host, content=smtp.coldmail.com
SystemOut     O  added StringRefAddr: type=mail.debug, content=true
SystemOut     O  added StringRefAddr: type=mail.pop3s.class, content=com.sun.mail.pop3.POP3SSLStore
SystemOut     O  added StringRefAddr: type=mail.from, content=smith@coldmail.com
SystemOut     O  added StringRefAddr: type=mail.smtp.class, content=com.sun.mail.smtp.SMTPTransport
SystemOut     O  added StringRefAddr: type=mail.smtps.class, content=com.sun.mail.smtp.SMTPSSLTransport
SystemOut     O  added StringRefAddr: type=mail.imap.class, content=com.sun.mail.imap.IMAPStore
SystemOut     O  added StringRefAddr: type=mail.smtp.user, content=smith
SystemOut     O  added StringRefAddr: type=mail.pop3.class, content=com.sun.mail.pop3.POP3Store
SystemOut     O  added StringRefAddr: type=mail.mime.address.strict, content=true


SystemOut     O DEBUG: JavaMail version 1.4ea
SystemOut     O DEBUG: java.io.FileNotFoundException: 
C:\IBM\WebSphere\AppServer\java\jre\lib\javamail.providers 
(The system cannot find the file specified.)
SystemOut     O DEBUG: !anyLoaded
SystemOut     O DEBUG: not loading resource: /META-INF/javamail.providers
SystemOut     O DEBUG: successfully loaded resource: /META-INF/javamail.default.providers
SystemOut     O DEBUG: Tables of loaded providers
SystemOut     O DEBUG: Providers Listed By Class Name: 
     {com.sun.mail.smtp.SMTPSSLTransport=javax.mail.Provider
[TRANSPORT,smtps,com.sun.mail.smtp.SMTPSSLTransport,Sun Microsystems, Inc], 
com.sun.mail.smtp.SMTPTransport=javax.mail.Provider
[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Sun Microsystems, Inc], 
com.sun.mail.imap.IMAPSSLStore=javax.mail.Provider
[STORE,imaps,com.sun.mail.imap.IMAPSSLStore,Sun Microsystems, Inc], 
com.sun.mail.pop3.POP3SSLStore=javax.mail.Provider
[STORE,pop3s,com.sun.mail.pop3.POP3SSLStore,Sun Microsystems, Inc], 
com.sun.mail.imap.IMAPStore=javax.mail.Provider
[STORE,imap,com.sun.mail.imap.IMAPStore,Sun Microsystems, Inc], 
com.sun.mail.pop3.POP3Store=javax.mail.Provider
[STORE,pop3,com.sun.mail.pop3.POP3Store,Sun Microsystems, Inc]}
SystemOut     O DEBUG: Providers Listed By Protocol: 
{imaps=javax.mail.Provider[STORE,imaps,com.sun.mail.imap.IMAPSSLStore,Sun Microsystems,Inc], 
imap=javax.mail.Provider[STORE,imap,com.sun.mail.imap.IMAPStore,Sun Microsystems, Inc], 
smtps=javax.mail.Provider[TRANSPORT,smtps,com.sun.mail.smtp.SMTPSSLTransport,Sun Microsystems,Inc], 
pop3=javax.mail.Provider[STORE,pop3,com.sun.mail.pop3.POP3Store,Sun Microsystems, Inc], 
pop3s=javax.mail.Provider[STORE,pop3s,com.sun.mail.pop3.POP3SSLStore,Sun Microsystems, Inc], 
smtp=javax.mail.Provider[TRANSPORT,smtp,com.sun.mail.smtp.SMTPTransport,Sun Microsystems, Inc]}
SystemOut     O DEBUG: successfully loaded resource: /META-INF/javamail.default.address.map
SystemOut     O DEBUG: !anyLoaded
SystemOut     O DEBUG: not loading resource: /META-INF/javamail.address.map
SystemOut     O DEBUG: java.io.FileNotFoundException: 
     C:\IBM\WebSphere\AppServer\java\jre\lib\javamail.address.map 
     (The system cannot find the file specified.)
SystemOut     O *** In SessionFactory.setPasswordAuthentication, 
   TRANSPORT PasswordAuthentication is based on:
SystemOut     O  url=smtp://smith@smtp.coldmail.com
SystemOut     O  user=smith
SystemOut     O  password=****
SystemOut     O *** In SessionFactory.getObjectInstance, session properties:
SystemOut     O  mail.transport.protocol=smtp
SystemOut     O  mail.imaps.class=com.sun.mail.imap.IMAPSSLStore
SystemOut     O  mail.smtp.host=smtp.coldmail.com
SystemOut     O  mail.debug=true

SystemOut     O  mail.pop3s.class=com.sun.mail.pop3.POP3SSLStore
SystemOut     O  mail.from=smith@coldmail.com
SystemOut     O  mail.smtp.class=com.sun.mail.smtp.SMTPTransport
SystemOut     O  mail.smtps.class=com.sun.mail.smtp.SMTPSSLTransport
SystemOut     O  mail.imap.class=com.sun.mail.imap.IMAPStore
SystemOut     O  mail.smtp.user=smith
SystemOut     O  mail.pop3.class=com.sun.mail.pop3.POP3Store
SystemOut     O  mail.mime.address.strict=true
SystemOut     O DEBUG: mail.smtp.class property exists and points to com.sun.mail.smtp.SMTPTransport
SystemOut     O DEBUG SMTP: useEhlo true, useAuth false
SystemOut     O DEBUG SMTP: trying to connect to host "smtp.coldmail.com", port 25, isSSL false


javax.mail.MessagingException: Unknown SMTP host: smtp.coldmail.com;
  nested exception is:
 java.net.UnknownHostException: smtp.coldmail.com
 at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1280)
 at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:370)
 at javax.mail.Service.connect(Service.java:275)
 at javax.mail.Service.connect(Service.java:156)
 at javax.mail.Service.connect(Service.java:105)
 at javax.mail.Transport.send0(Transport.java:168)
 at javax.mail.Transport.send(Transport.java:98)
 at com.ibm.ws.mail.ut.TestServlet.doTask(TestServlet.java:104)
 at com.ibm.ws.mail.ut.TestServlet.doGet(TestServlet.java:65)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
 at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
 at com.ibm.ws.webcontainer.servlet.ServletWrapper.service(ServletWrapper.java:1397)
 at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:759)
 at com.ibm.ws.webcontainer.servlet.ServletWrapper.handleRequest(ServletWrapper.java:429)
 at com.ibm.ws.webcontainer.servlet.ServletWrapperImpl.handleRequest(ServletWrapperImpl.java:175)
 at com.ibm.ws.webcontainer.webapp.WebApp.handleRequest(WebApp.java:3512)
 at com.ibm.ws.webcontainer.webapp.WebGroup.handleRequest(WebGroup.java:273)
 at com.ibm.ws.webcontainer.WebContainer.handleRequest(WebContainer.java:896)
 at com.ibm.ws.webcontainer.WSWebContainer.handleRequest(WSWebContainer.java:1530)
 at com.ibm.ws.webcontainer.channel.WCChannelLink.ready(WCChannelLink.java:161)
 at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleDiscrimination(HttpInboundLink.java:455)
 at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.handleNewInformation(HttpInboundLink.java:384)
 at com.ibm.ws.http.channel.inbound.impl.HttpInboundLink.ready(HttpInboundLink.java:272)
 at com.ibm.ws.tcp.channel.impl.NewConnectionInitialReadCallback.sendToDiscriminators(NewConnectionInitialReadCallback.java:214)
 at com.ibm.ws.tcp.channel.impl.NewConnectionInitialReadCallback.complete(NewConnectionInitialReadCallback.java:113)
 at com.ibm.ws.tcp.channel.impl.AioReadCompletionListener.futureCompleted(AioReadCompletionListener.java:165)
 at com.ibm.io.async.AbstractAsyncFuture.invokeCallback(AbstractAsyncFuture.java:217)
 at com.ibm.io.async.AsyncChannelFuture.fireCompletionActions(AsyncChannelFuture.java:161)
 at com.ibm.io.async.AsyncFuture.completed(AsyncFuture.java:138)
 at com.ibm.io.async.ResultHandler.complete(ResultHandler.java:202)
 at com.ibm.io.async.ResultHandler.runEventProcessingLoop(ResultHandler.java:766)
 at com.ibm.io.async.ResultHandler$2.run(ResultHandler.java:896)
 at com.ibm.ws.util.ThreadPool$Worker.run(ThreadPool.java:1487)
Caused by: java.net.UnknownHostException: smtp.coldmail.com
 at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:196)
 at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
 at java.net.Socket.connect(Socket.java:519)
 at java.net.Socket.connect(Socket.java:469)
 at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:232)
 at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:189)
 at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1250)
 ... 32 more 

This output illustrates a connection failure to a Simple Mail Transfer Protocol (SMTP) server because a fictitious name, smtp.coldmail.com, is specified as the server name.

The following list provides tips on reading the previous sample of debugger output:

• The lines headed by DEBUG are printed by the mail provider at run time, while the two lines headed by *** are printed by the application server at run time.

• In the second paragraph of code, the first few lines state that some configuration files are skipped. The mail component attempts to load a number of configuration files from different locations at run time. All those files are not required. If a required file cannot be accessed, however, the mail component creates an exception. In this sample, there is no exception and the third-line announces that default providers are loaded.

• The next few lines, headed by either Providers Listed by Class Name or Providers Listed by Protocols, show the protocol providers that are loaded. The six providers listed are the default protocol providers that come under the built-in mail provider for the application server. If we install special service providers, and these providers are used in the current mail session, those providers are listed here with the default providers.

• The two lines headed by *** and the few lines below them are printed by the application server to show the configuration properties of the current mail session. Although these properties are listed by their internal name rather than the name you establish in the administrative console, we can recognize the relationships between them. For example, the mail.store.protocol property corresponds to the Protocol property in the Incoming ail Properties section of the console panel for mail session configuration. Review the listed properties and values to verify that they correspond.

• The few lines above the exception stack show the mail activities when sending a message. First, the JavaMail API recognizes that the transport protocol is set to SMTP and that the com.sun.mail.smtp.SMTPTransport provider exists. Next, the output log displays the useEhlo and useAuth parameters, which are used by SMTP. Finally, the log shows the SMTP provider trying to connect to the smtp.coldmail.com mail server.

• The output log show the exception stack next. This data indicates that the specified mail server either does not exist or is not functioning.

Use High Performance Extensible Logging to troubleshoot applications