Windows Server 2008 R2. Exchange Server 2010 SP3.
Recently we have had a half dozen instances where people in another domain (some using Exchange Servers and others using other servers) could not get mail to our domain. When analyzing at our end I found that nothing was coming in from them (our firewall logged no SMTP traffic from them). After the first domain was able to "fix" the issue by resetting or refreshing their DNS, I began to mention that to others. They did the same and the problem was "fixed." Other senders on Exchange Servers used the following procedure to fix the issue:
http://www.noelpulis.com/fix-exhcange-2010-error-451-440-error-dns-query-failed/
My question is, WHAT could be the cause of email servers not being able to reach us such that refreshing or resetting the DNS "fixed" it? I did make some changes in our DNS records a few months ago, but none involved an IP address change. Below is what our DNS records look like:
| www | 7200 |
70.88.185.37 |
| @ (None) | 7200 |
70.88.185.37 |
| * (All Others) | 7200 | none |
| data .goodnewsjail.org | 7200 | 74.94.213.108 |
| extranet .goodnewsjail.org | 7200 |
74.94.213.107 |
| grading .goodnewsjail.org | 7200 |
74.94.213.105 |
| mail .goodnewsjail.org | 7200 |
74.94.213.106 |
| new .goodnewsjail.org | 7200 |
70.88.185.37 |
| old .goodnewsjail.org | 7200 |
74.94.213.108 |
| re .goodnewsjail.org | 7200 | 74.94.213.109 |
Doug Pruiett Good News Jail & Prison Ministry Richmond, Virginia www.goodnewsjail.org