如不存在mx记录，则解析异常

GoogleCodeExporter commented 9 years ago

What steps will reproduce the problem?
$ host -t mx test.google.com 42.120.21.30
;; connection timed out; no servers could be reached

What is the expected output? What do you see instead?
$ host -t mx test.google.com 8.8.4.4
Using domain server:
Name: 8.8.4.4
Address: 8.8.4.4#53
Aliases:

Host test.google.com not found: 3(NXDOMAIN)

若不存在mx记录，正常应返回nxdomain，而不是连接超时

What version of the product are you using? On what operating system?
Linux

Please provide any additional information below.
N/A

Original issue reported on code.google.com by unic...@gmail.com on 23 Jul 2014 at 4:41

GoogleCodeExporter commented 9 years ago

这个问题应该不能算问题吧。

由于是不存在记录，正常我们应该会返回一个空值，不过可��
�这个返回时间比较长。

Original comment by opene...@gmail.com on 25 Jul 2014 at 7:49

GoogleCodeExporter commented 9 years ago

事实上会影响到解析效率，因为nxdomain的返回是会被cache的，�
��下次再解析的时候可以直接返回nxdomain。而连接timeout的话不
会被cache，导致每次遇到一样的解析都需要等超时。aaaa记录��
�有类似情况。

Original comment by unic...@gmail.com on 25 Jul 2014 at 8:27

appleseedez / openerdns

如不存在mx记录，则解析异常 #121