我正在设置一个Bugzilla服务器 . 我在配置期间在Bugzilla页面上提交电子邮件传递方法说明时遇到以下错误 .

smtpserver的新值无效：无法连接到10.71.2.16 .

Email delivery method description

mail_delivery_method: SMTP
mailfrom: bugzilla@mydomain.com
use_mailer_queue: off
smtpserver: 10.71.2.16 
(I have also tried putting domain name, all ports such as 25, 465, 587)
smtp_username: bugzilla@mydomain.com
smtp_password: <password for user bugzilla@mydomain.com>
smtp_ssl: I have tried On and Off both but no sucsess
smtp_debug: On (but not sure where it generates logs. 
Checked /var/log/apache2/. But nothing over there.)

My environment

Ubuntu: 16.04 Server (Internal Server IP: 10.71.6.45)
Bugzilla: 5.0.3 (Internal Server IP: 10.71.6.45)
SMTP: Zimbra Release 8.0.6_GA_5922.RHEL6_64 RHEL6_64 FOSS edition. 
(Internal Server IP: 10.71.2.16)
This Zimbra is hosted on a remote server (10.71.2.16) in Intranet. 
It is sending and receiving emails successfully from long time without any issues.

/var/log/zimbra.log on (server 10.71.2.16 where SMTP is hosted)

Dec  1 00:25:22 email postfix/smtps/smtpd[18064]: connect from unknown[10.71.6.45]
Dec  1 00:25:22 email postfix/smtps/smtpd[18064]: SSL_accept error from unknown[10.71.6.45]: lost connection
Dec  1 00:25:22 email postfix/smtps/smtpd[18064]: lost connection after CONNECT from unknown[10.71.6.45]
Dec  1 00:25:22 email postfix/smtps/smtpd[18064]: disconnect from unknown[10.71.6.45]

/var/log/maillog (on server 10.71.2.16 where SMTP is hosted)

Dec  1 00:24:36 email postfix/smtps/smtpd[18064]: connect from unknown[10.71.6.45]
Dec  1 00:24:36 email postfix/smtps/smtpd[18064]: SSL_accept error from unknown[10.71.6.45]: lost connection
Dec  1 00:24:36 email postfix/smtps/smtpd[18064]: lost connection after CONNECT from unknown[10.71.6.45]
Dec  1 00:24:36 email postfix/smtps/smtpd[18064]: disconnect from unknown[10.71.6.45]

However when I am sending email from command prompt with below command emails are getting delivered

echo“这是电子邮件正文 . 此电子邮件是使用SMTP服务器10.71.2.16从Ubuntu Server 10.71.6.45发送的”| mailx -v -r“bugzilla@mydomain.com”-s“Bugzilla测试邮件 - 这是主题”-S smtp =“10.71.2.16”-S smtp-use-starttls -S smtp-auth = login -S smtp -auth-user =“bugzilla@mydomain.com”-S smtp-auth-password =“bugzilla@mydomain.com-emailid-password”-S ssl-verify = ignore test@mydomain.com

/var/www/html/bugzilla/Bugzilla/Mailer.pm snippet

if ($method eq "SMTP") {
    my ($host, $port) = split(/:/, Bugzilla->params->{'smtpserver'}, 2);
    $transport = Bugzilla->request_cache->{smtp} //=
      Email::Sender::Transport::SMTP::Persistent->new({
        host  => $host,
        defined($port) ? (port => $port) : (),
        sasl_username => Bugzilla->params->{'smtp_username'},
        sasl_password => Bugzilla->params->{'smtp_password'},
        helo => $hostname,
        ssl => Bugzilla->params->{'smtp_ssl'},
        debug => Bugzilla->params->{'smtp_debug'} });
}

我尝试了所有可能的组合 . 但它总是在Bugzilla中给出以下错误

smtpserver的新值无效：无法连接到10.71.2.16 .

我做错了什么或者我错过了什么？

email smtp bugzilla postfix zimbra