Exim说DNS查询成功了，还说“主机查找没有完成”

我试图发送自动通知电子邮件给我的网站的用户。 这些电子邮件通过自定义守护进程发送给用户，自定义守护进程通过进程4发送它们.Exim的作用就是将邮件转发到与收件人地址关联的邮件服务器。 所有传出的电子邮件必须中继。 没有本地电子邮件，也没有收到邮件。

但是，当我尝试发送电子邮件时，守护进程总是得到以下响应：

com.sun.mail.smtp.SMTPAddressFailedException: 451 Temporary local problem - please try later 

在/var/log/exim4/mainlog ，我有以下几行

 2014-09-09 22:30:50 no host name found for IP address 10.0.2.2 2014-09-09 22:30:50 H=(lotp-lanbox) [10.0.2.2] F=<[email protected]> temporarily rejected RCPT <[email protected]>: host lookup did not complete 

（请注意，10.0.2.2是安装了发件人守护程序的主机的IP地址。）

• Exim下降vs拒绝坏的收件人
• 修复可怜的电子邮件
• 发送批量电子邮件的最佳方式是什么？
• 如何将换行符（\ n）放在自动回复的文本中？
• 带有SRS守护进程的exim4configuration

这个消息很奇怪，但缺乏细节。 这是另一个我已经启动的debugging命令：

 user@host:~$ exim4 -bt -d-resolver [email protected] Exim version 4.82 uid=0 gid=0 pid=14035 D=fbb95cfd Berkeley DB: Berkeley DB 5.3.28: (September 9, 2013) Support for: crypteq iconv() IPv6 GnuTLS move_frozen_messages DKIM Lookups (built-in): lsearch wildlsearch nwildlsearch iplsearch cdb dbm dbmjz dbmnz dnsdb dsearch nis nis0 passwd Authenticators: cram_md5 plaintext Routers: accept dnslookup ipliteral manualroute queryprogram redirect Transports: appendfile/maildir/mailstore autoreply lmtp pipe smtp Fixed never_users: 0 Size of off_t: 8 Compiler: GCC [4.8.2] Library version: GnuTLS: Compile: 2.12.23 Runtime: 2.12.23 Library version: PCRE: Compile: 8.31 Runtime: 8.31 2012-07-06 Total 13 lookups WHITELIST_D_MACROS: "OUTGOING" TRUSTED_CONFIG_LIST: "/etc/exim4/trusted_configs" changed uid/gid: forcing real = effective uid=0 gid=0 pid=14035 auxiliary group list: <none> seeking password data for user "uucp": cache not available getpwnam() succeeded uid=10 gid=10 changed uid/gid: calling tls_validate_require_cipher uid=109 gid=116 pid=14036 auxiliary group list: <none> tls_validate_require_cipher child 14036 ended: status=0x0 configuration file is /var/lib/exim4/config.autogenerated log selectors = 00000ffc 00632001 trusted user admin user seeking password data for user "mail": cache not available getpwnam() succeeded uid=8 gid=8 user name "root" extracted from gecos field "root" originator: uid=0 gid=0 login=root name=root sender address = root@dev Address testing: uid=0 gid=116 euid=0 egid=116 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Testing [email protected] >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Considering [email protected] >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> routing [email protected] --------> hubbed_hosts router <-------- local_part=foobar domain=romandie.com checking domains expansion of "${if exists{/etc/exim4/hubbed_hosts}{partial-lsearch;/etc/exim4/hubbed_hosts}fail}" forced failure: assume not in this list hubbed_hosts router skipped: domains mismatch --------> dnslookup_relay_to_domains router <-------- local_part=foobar domain=romandie.com checking domains romandie.com in "@:localhost"? no (end of list) romandie.com in "*"? yes (matched "*") romandie.com in "! +local_domains : +relay_to_domains"? yes (matched "+relay_to_domains") R: dnslookup_relay_to_domains for [email protected] calling dnslookup_relay_to_domains router dnslookup_relay_to_domains router called for [email protected] domain = romandie.com DNS lookup of romandie.com (MX) succeeded dnslookup_relay_to_domains router: defer for [email protected] message: host lookup did not complete [email protected] cannot be resolved at this time: host lookup did not complete search_tidyup called >>>>>>>>>>>>>>>> Exim pid=14035 terminating with rc=1 >>>>>>>>>>>>>>>> 

下面是我看起来特别怪异的摘录（从输出结尾开始）：

 dnslookup_relay_to_domains router called for [email protected] domain = romandie.com DNS lookup of romandie.com (MX) succeeded dnslookup_relay_to_domains router: defer for [email protected] message: host lookup did not complete [email protected] cannot be resolved at this time: host lookup did not complete 

如何才能成功和不完整的DNS查找？ 我究竟做错了什么？

我已经尝试使用安装了exim4的机器进行dig ，并且结果对我来说很好：

 user@host:~$ dig mx romandie.com ;; Warning: Message parser reports malformed message packet. ; <<>> DiG 9.9.5-3-Ubuntu <<>> mx romandie.com ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 36151 ;; flags: qr aa rd ra ad; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1 ;; WARNING: Message has 1 extra bytes at end ;; QUESTION SECTION: ;romandie.com. IN MX ;; ANSWER SECTION: romandie.com. 3600 IN A 37.35.105.169 romandie.com. 3600 IN A 37.35.105.166 ;; Query time: 19 msec ;; SERVER: 10.0.2.3#53(10.0.2.3) ;; WHEN: Tue Sep 09 23:14:45 UTC 2014 ;; MSG SIZE rcvd: 63 

查找本身看起来很好。

为什么exim说同时成功和失败呢？