javax.mail.MessagingException：无法连接到 SMTP 主机：172.16.100.185，端口：25；

Question

我编写了一个简单的程序来使用 Java API 发送电子邮件。下面是代码。接下来是我收到的错误消息。

        String host = "172.16.100.185";
        final String user = "anand.rajendran@*****.net";

        String to = "anand.rajendran@*****.net";

        // Get the session object
        Properties props = new Properties();
        props.put("mail.smtp.host", host);
        //props.put("mail.smtp.port", "587");


        Session session = Session.getDefaultInstance(props,null);

        // Compose the message
        try {
            MimeMessage message = new MimeMessage(session);
            message.setFrom(new InternetAddress(user));
            message.addRecipient(Message.RecipientType.TO, new InternetAddress(to));
            message.setSubject("My subject");
            message.setText("This is simple program of sending email using JavaMail API");

            // send the message
            Transport.send(message);

        } catch (MessagingException e) {
            e.printStackTrace();
        }

错误：

javax.mail.MessagingException: Could not connect to SMTP host: 172.16.100.185, port: 25;
  nested exception is:
    java.net.SocketException: Permission denied: connect
    at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:1282)
    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.photon.bigdata.heartbeat.service.impl.HeartBeatServiceImpl.sendFailureReportEmail(HeartBeatServiceImpl.java:167)
    at com.photon.bigdata.heartbeat.controller.HeartBeatController.sendReport(HeartBeatController.java:62)
    at com.photon.bigdata.heartbeat.controller.HeartBeatController.main(HeartBeatController.java:33)
Caused by: java.net.SocketException: Permission denied: connect
    at java.net.DualStackPlainSocketImpl.connect0(Native Method)
    at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
    at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
    at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
    at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
    at java.net.PlainSocketImpl.connect(Unknown Source)
    at java.net.SocksSocketImpl.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    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)
    ... 9 more

仅供参考，我也尝试了以下方法。

1) 我尝试使用端口号：25、465 和 587。

props.put("mail.smtp.port", "465");
props.put("mail.smtp.port", "587");

2) 检查主机中的 sendMail 状态

[root@stormcluster1 ~]# service sendmail status
sendmail (pid  13898) is running...
sm-client (pid  13910) is running...

3) 在主机中，我检查了 SMTP 服务器是否正在侦听端口 25

[root@stormcluster1 ~]# lsof -i :25
COMMAND    PID USER   FD   TYPE  DEVICE SIZE/OFF NODE NAME
sendmail 13898 root    4u  IPv4 2172898      0t0  TCP localhost:smtp (LISTEN)

4) 能够从 Linux 终端发送电子邮件

我成功地使用以下命令从 SMPT 服务器已启动的 linux 邮箱和运行向我的电子邮件地址发送了一封电子邮件。邮件-s "from 44 with sudo access" anand.rajendran@*****.net

Answer 1

发现一些参考资料表明这是 Java-7 相关的：
JavaMail API to iMail -- java.net.SocketException: Permission denied: connect

https://confluence.atlassian.com/display/STASHKB/Mail+Server+Connection+Failed+With+'java.net.SocketException%3A+Permission+denied%3A+connect.'+异常

这些页面提供了解决方法。

Answer 2

问题出在安装的 SMPT 服务器的配置文件上。我将我的 java 应用程序指向另一台机器，其中另一个 SMTP 服务器是运行。它运作良好。 :) 感谢大家的时间和努力！干杯

javax.mail.MessagingException：无法连接到 SMTP 主机：172.16.100.185，端口：25；

javax.mail.MessagingException: Could not connect to SMTP host: 172.16.100.185, port: 25;

java

email

sendmail

jakarta-mail

1) 我尝试使用端口号：25、465 和 587。

2) 检查主机中的 sendMail 状态

3) 在主机中，我检查了 SMTP 服务器是否正在侦听端口 25

4) 能够从 Linux 终端发送电子邮件