oracle - ORA-29278 : SMTP transient error: Service not available when running UTL_MAIL

Question

我们计划安装 UTL_MAIL 包，目前正在开发环境中测试安装步骤。
成功安装 UTL_MAIL 包脚本并创建足够的 PUBLIC Synonyms 和 Grants 后，
运行下面的测试匿名块时，我们收到错误 ORA-29278:

BEGIN 

    UTL_MAIL.SEND(sender     => 'xxx@oracle.com'
                , recipients => 'Migs.Isip.23@gmail.com'
                , subject    => 'Testmail'
                , message    => 'Hello');

END;

错误消息的完整详细信息:

ORA-29278: SMTP transient error: 421 4.3.2 Service not available
ORA-06512: at "SYS.UTL_MAIL", line 662
ORA-06512: at "SYS.UTL_MAIL", line 679
ORA-06512: at line 3
29278. 00000 -  "SMTP transient error: %s"
*Cause:    A SMTP transient error occurred.
*Action:   Correct the error and retry the SMTP operation.    

根据相关链接( Send Email Using PLSQL )的研究，
我可能需要设置正确的访问控制列表 (ACL) 才能使其工作。但是，在执行下面的脚本时，我仍然遇到相同的错误。

DECLARE
   -- ACL name to be used for email access reuse the same value for all 
   -- future calls
   l_acl         VARCHAR2 (30) := 'utl_smtp.xml';
   -- Oracle user to be given permission to send email
   l_principal   VARCHAR2 (30) := 'APPS';
   -- Name of email server
   g_mailhost    VARCHAR2 (60) := 'smtprelay.xxxxx.com';
   l_cnt         INTEGER;

   PROCEDURE validate_smtp_server
   AS
      l_value       v$parameter.VALUE%TYPE;
      l_parameter   v$parameter.name%TYPE := 'smtp_out_server';
   BEGIN

      SELECT VALUE
        INTO l_value
        FROM v$parameter
       WHERE name = l_parameter;

      IF l_value IS NULL
      THEN
         raise_application_error (
            -20001
          ,    'Oracle parameter '
            || l_parameter
            || ' has not been set'
            || UTL_TCP.crlf
            || 'it s/b smtprelay.alorica.com'
         );
      END IF;

      DBMS_OUTPUT.put_line ('parameter ' || l_parameter || ' value is ' ||     l_value);

   END validate_smtp_server;

   PROCEDURE create_if_needed (p_acl IN VARCHAR2)
   AS
      l_cnt   INTEGER;
   BEGIN

      SELECT COUNT (*) c
        INTO l_cnt
        FROM dba_network_acls a
       WHERE SUBSTR (acl, INSTR (acl, '/', -1) + 1) = p_acl;

      IF l_cnt = 0
      THEN
         DBMS_OUTPUT.put_line ('creating acl ' || p_acl);
         DBMS_NETWORK_ACL_ADMIN.create_acl (
            acl         => p_acl
          , description => 'Allow use of utl_smtp'
          , principal   => l_principal
          , is_grant    => TRUE
          , privilege   => 'connect'
         );

         DBMS_NETWORK_ACL_ADMIN.assign_acl (acl => p_acl, HOST => g_mailhost);
         COMMIT;
      ELSE
         DBMS_OUTPUT.put_line (p_acl || ' acl already exists');
      END IF;

   END create_if_needed;

   PROCEDURE add_if_needed (
      p_principal   IN VARCHAR2
    , p_acl         IN VARCHAR2
   )
   AS
      l_cnt   INTEGER;
   BEGIN

      SELECT COUNT (*) c
        INTO l_cnt
        FROM dba_network_acl_privileges
       WHERE SUBSTR (acl, INSTR (acl, '/', -1) + 1) = p_acl
         AND principal = p_principal;

      IF l_cnt = 0
      THEN
         DBMS_NETWORK_ACL_ADMIN.add_privilege (
            acl       => 'utl_smtp.xml'
          , principal => p_principal
          , is_grant  => TRUE
          , privilege => 'connect'
         );
         COMMIT;
         DBMS_OUTPUT.put_line ('access to ' || p_acl || ' added for ' ||     p_principal);
      ELSE
         DBMS_OUTPUT.put_line (p_principal || ' already has access to ' || p_acl);
      END IF;

   END add_if_needed;
BEGIN

   EXECUTE IMMEDIATE 'grant execute on utl_mail to ' || l_principal;

   create_if_needed (p_acl => l_acl);
   add_if_needed (p_principal => l_principal, p_acl => l_acl);
   DBMS_OUTPUT.put_line ('Verification SQL:');
   DBMS_OUTPUT.put_line ('    SELECT * FROM dba_network_acls;');
   DBMS_OUTPUT.put_line ('    SELECT * FROM dba_network_acl_privileges;');
   COMMIT;
   validate_smtp_server;
END;

为此，我还可以采取哪些其他步骤或需要向 DBA 提供哪些其他说明？

Oracle 数据库版本:

Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
PL/SQL Release 11.2.0.4.0 - Production
"CORE   11.2.0.4.0  Production"
TNS for Solaris: Version 11.2.0.4.0 - Production
NLSRTL Version 11.2.0.4.0 - Production

非常感谢。

Answer 1

我能够通过联系我们的系统管理员并询问邮件服务器的详细信息来解决这个问题。
事实证明，如果我们只在内部发送电子邮件，我们建议使用不同的服务器 mail.xxx.xxx.xxxx因为它不会被防火墙阻止。
另一方面，如果我们要向外部发送电子邮件，则涉及另一台服务器 smtprelay.xxxxx.com这涉及将要发送到的外部服务器列入白名单的额外步骤。

当我登记时 V$PARAMETER ，我们使用的是 smtprelay.xxxxx.com服务器并决定尝试另一台服务器 mail.xxx.xxx.xxxx .

我发出了如下 Alter 命令:

alter system set smtp_out_server = 'mail.xxx.xxx.xxxx';

并运行匿名块并能够成功接收电子邮件。

BEGIN 

    UTL_MAIL.SEND(sender     => 'xxx@oracle.com'
                , recipients => 'Migs.Isip.23@gmail.com'
                , subject    => 'Testmail'
                , message    => 'Hello');

END;