java.net.SocketException: Broken pipe with SMTP

Question

I got strange behavior when my application tries to send an email.

20:59:08,926 ERROR [release.com.mycompany.mail.GenericMail] (EJB default - 5) [MY_EJB INBOUND] Sending message failed!: javax.mail.MessagingException: Can't send command to SMTP host;
  nested exception is:
    java.net.SocketException: Broken pipe
    at com.sun.mail.smtp.SMTPTransport.sendCommand(SMTPTransport.java:2106) [mail-1.4.4-redhat-2.jar:1.4.4-redhat-2]
    at com.sun.mail.smtp.SMTPTransport.sendCommand(SMTPTransport.java:2093) [mail-1.4.4-redhat-2.jar:1.4.4-redhat-2]
    at com.sun.mail.smtp.SMTPTransport.close(SMTPTransport.java:1184) [mail-1.4.4-redhat-2.jar:1.4.4-redhat-2]
    at javax.mail.Transport.send0(Transport.java:197) [mail-1.4.4-redhat-2.jar:1.4.4-redhat-2]
    at javax.mail.Transport.send(Transport.java:124) [mail-1.4.4-redhat-2.jar:1.4.4-redhat-2]
    at com.mycompany.MailUtils.sendMail(MailUtils.java:258) [classes:]

Before this exception some timeout exception has been thrown:

    20:57:50,291 ERROR [org.jboss.as.ejb3] (EJB default - 9) [ ] JBAS014122: Error during
retrying timeout for timer: [id=6be904b5-c1ef-4f0e-a277-d4c9f93e21b3 timedObjectId=SOME_EJB 
auto-timer?:false persistent?:false timerService=org.jboss.as.ejb3.timerservice.TimerServiceImpl@99fdab1 initialExpiration=/* date */ 00:00:00 UTC 2015 intervalDuration(in milli sec)=0 nextExpiration=/* other date */ 21:00:00 UTC 2015 
timerState=RETRY_TIMEOUT: javax.ejb.EJBTransactionRolledbackException: JBAS014373: 
EJB 3.1 PFD2 4.8.5.5.1 concurrent access timeout on org.jboss.invocation.InterceptorContext$Invocation@66668127 - could not obtain lock within 5000MILLISECONDS

To be honest i don't know whats happened. I got these kind of exception for 5 hours. I want to know whats happened and be able to avoid exceptions in future.

UPDATE 1

SOME_EJB is an ejb with works with timerService. Runs every 3 minutes, when the conditions are met sends an email.

My only idea is that there was some network/database issue and it caused that single execution of task took more than 3 minutes.

MailUtils is a @Stateless ejb

Answer 1

Is the mail sent or not?

It looks like JavaMail is closing the connection to the mail server when the exception occurs. If a previous error caused the server to drop the connection immediately, JavaMail may be getting this exception while trying to send the SMTP BYE command before closing the connection.

Turn on JavaMail Session debugging to see what error the server might have reported before this exception occurs.