Jenkins Email Plugin : Could not connect to SMTP host: smtp.gmail.com, port: 465;

Question

I am trying to configure Email notifications for a Jenkins build job(Using the Mailer Plugin). I'm using Jenkins inside TomEE. When I tried to test my configuration, I got the javax.mail.MessagingException:

Failed to send out e-mail

javax.mail.MessagingException: Could not connect to SMTP host: smtp.gmail.com, port: 465;
nested exception is:
java.net.ConnectException: Connection timed out: connect

at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1934)

at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:638)

at javax.mail.Service.connect(Service.java:317)

at javax.mail.Service.connect(Service.java:176)

at javax.mail.Service.connect(Service.java:125)

at javax.mail.Transport.send0(Transport.java:194)

at javax.mail.Transport.send(Transport.java:124)

at hudson.tasks.Mailer$DescriptorImpl.doSendTestMail(Mailer.java:581)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

at java.lang.reflect.Method.invoke(Method.java:498)

at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:335)

at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:175)

at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:108)

at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:124)

at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:58)

at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:746)

at org.kohsuke.stapler.Stapler.invoke(Stapler.java:876)

at org.kohsuke.stapler.MetaClass$5.doDispatch(MetaClass.java:236)

at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:58)

at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:746)

at org.kohsuke.stapler.Stapler.invoke(Stapler.java:876)

at org.kohsuke.stapler.Stapler.invoke(Stapler.java:649)

at org.kohsuke.stapler.Stapler.service(Stapler.java:238)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)

at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)

at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:135)

at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:126)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)

at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:80)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)

at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)

at hudson.security.UnwrapSecurityExceptionFilter.doFilter(UnwrapSecurityExceptionFilter.java:51)

at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)

at jenkins.security.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:117)

at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)

at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)

at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)

at org.acegisecurity.ui.rememberme.RememberMeProcessingFilter.doFilter(RememberMeProcessingFilter.java:142)

at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)

at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:271)

at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)

at jenkins.security.BasicHeaderProcessor.doFilter(BasicHeaderProcessor.java:93)

at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)

at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:249)

at hudson.security.HttpSessionContextIntegrationFilter2.doFilter(HttpSessionContextIntegrationFilter2.java:67)

at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)

at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)

at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:171)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)

at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:49)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)

at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:82)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)

at org.kohsuke.stapler.DiagnosticThreadNameFilter.doFilter(DiagnosticThreadNameFilter.java:30)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)

at org.apache.tomee.catalina.OpenEJBValve.invoke(OpenEJBValve.java:44)

at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:614)

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)

at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956)

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436)

at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)

at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625)

at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)

at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)

at java.lang.Thread.run(Thread.java:745)

Caused by: java.net.ConnectException: Connection timed out: connect

at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)

at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:85)

at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)

at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)

at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)

at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)

at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)

at java.net.Socket.connect(Socket.java:589)

at sun.security.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:668)

at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:286)

at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:205)

at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1900)

... 82 more

I read about the new security feature of Jenkins where it doesn't allow sending of mails to a non-Jenkins user. So I tried again by adding the following in my catalina.properties:

hudson.tasks.MailSender.SEND_TO_UNKNOWN_USERS=true
hudson.tasks.MailSender.SEND_TO_USERS_WITHOUT_READ=true

I still got the same error.

Any help would be great. Thanks.

Answer 1

In my case, everything is working fine after restarting the Jenkins service by running the command systemctl restart jenkins in ubuntu 20.04 os.

Answer 2

I'm having the same issue. I verified it is actually not network or gmail issue assuming you have enabled unsecure app (using the password from app password). It is probably a bug or some configuration issue of Jenkins.

Here's my settings:

SMTP server: smtp.gmail.com
Use SMTP Authentication: true
User Name: myname@gmail.com
Password: password
Use SSL: true||false #tried both with different combination with TLS
Use TLS: true||false
SMTP Port: 587 || 465

I wrote a small program basically does the same thing, and ran it on the same server as Jenkins, and that works fine. So, it is not local network firewall or something.

The settings for my program are:

SMTP server: smtp.gmail.com
Use SMTP Authentication: true
User Name: myname@gmail.com
Password: password
Use SSL: true
SMTP Port: 587

My last work was to SSLPoking it using Java since jenkins is based on Java. I was succeeded using 465 port, but was not able to send using that port neither. I switch to use my own script and run shell script instead.

Answer 3

Configuring the email service can be a bit disturbing sometimes, so once you encounter some annoying issues as happened to me:

javax. mail.MessagingException: Could not connect to SMTP host: smtp.gmail.com, port: 465;

Or

javax.mail.AuthenticationFailedException: 535-5.7.8 Username and Password not accepted

If you encountered one of these issues it is most likely that you haven't allowed your email sender to send an email through this service so all you have to do is log in to your sender email then go to Mail settings -> Security -> Enable less secure app access

Click on Turn on access(not recommended) then turn it on

Also, make sure you have entered the right email and password, check Use SSL and make sure SMTP Port is 465.

If the error still persisting then it must be something related to your firewall stopping you from sending SMTP requests using Jenkins, so to solve this temporarily all I had to do is disable my Avast antivirus for an hour and test the configuration and it worked like charm.

If you have any issues feel free to comment on this answer and I would be so happy to help you

Answer 4

Caused by: java.net.ConnectException: Connection timed out: connect

This doesn't have anything to do with recent security changes to the Mailer plugin, or to settings in Gmail — it's saying that your Jenkins server cannot connect to smtp.gmail.com:465. Presumably due to some issue within your network, or a firewall rule, or blocking by your ISP.

You should check with your network administrator, and ask them whether there's a more appropriate SMTP server that you should be using.