90% of attacks start with a phish. It’s critical that IT admins and MSSPs have the right security in place to protect their end users from these phishing attacks. Check out our latest feature brief for tips and tricks to keep your employees off a hackers line!
Solved
Yahoo boucing email to our domain, claims "No MX or A records for "ourdomain.edu
Posted on 2011-03-21
Recently, some Yahoo emails to our domain have been bouncing back to users with a "No MX or A records for ourdomain.edu". This is an intermittent problem, and we haven't been able to reliably reproduce the problem. We are receiveing email from other sources.
Our MX records are on our name server, and I can verify that our full DNS records can be seen and retrieved when I check external sources like dnstools.com, mxtoolbox.com, network-tools.com. We are still waiting to hear back from yahoo tech support. Is there anything else I can do in the meanwhile?
Our MX records are on our name server, and I can verify that our full DNS records can be seen and retrieved when I check external sources like dnstools.com, mxtoolbox.com, network-tools.com. We are still waiting to hear back from yahoo tech support. Is there anything else I can do in the meanwhile?
-
4
2
- +2
9 Comments
What about PTR record for your mail server? is it configured?? check this also online... if it's not configured, ask your ISP to do it
This will more than likely be due to PTR as mentioned above. Use a SMTP smarthost?
http://support.microsoft.com/kb/303734 -shows you how to set up.
If your ISP is eclipse for example use SMTP.ECLIPSE.CO.UK
Hope this helps
http://support.microsoft.com/kb/303734 -shows you how to set up.
If your ISP is eclipse for example use SMTP.ECLIPSE.CO.UK
Hope this helps
Check if your domain is on a blacklist? http://www.blacklistalert.org/
Also, can you provide us with the NDR email header?
Also, can you provide us with the NDR email header?
Active today
Double cheked: Yes, we have a PTR record for the mail server. No, we are not on any blacklists.
I'll see if I can get a hold of the NDR header - so far they've just been forwarding me the text of the message.
We did get a hold of someone at AT&T last week, and they have a known problem with people sending messages to external addresses.
I'll see if I can get a hold of the NDR header - so far they've just been forwarding me the text of the message.
We did get a hold of someone at AT&T last week, and they have a known problem with people sending messages to external addresses.
I wonder if there is a network reliability issue to your DNS servers. Is it possible that rarely, a DNS lookup is failing, or your server is not consisently providing the DNS info? As a start, you could ping your DNS servers (from an outside network at an alternate location, from an alternate ISP obviously) for an extended period of time. See if you get any packet loss, and what the latency is like.
Also, have you double checked your DNS using services like: http://www.intodns.com/ & http://www.mxtoolbox.com/SuperTool.aspx & http://dnscog.com/ ?? They may help you find the problem. You never know, maybe your TTL values are set extremely low, and the DNS servers are polling your server more frequently than it can handle.
Also, have you double checked your DNS using services like: http://www.intodns.com/ & http://www.mxtoolbox.com/SuperTool.aspx & http://dnscog.com/ ?? They may help you find the problem. You never know, maybe your TTL values are set extremely low, and the DNS servers are polling your server more frequently than it can handle.
Active today
I'll setup the ping for DNS servers. Seems fine so far, but we'll keep an eye on it.
We're getting green checkmarks on everything when checking the outside sites like intodns.com, mxtoolbox.com, and dnscog.com except SOA Expire was over suggested limits and we dont' currently have SPF record, which I will add.
We're getting green checkmarks on everything when checking the outside sites like intodns.com, mxtoolbox.com, and dnscog.com except SOA Expire was over suggested limits and we dont' currently have SPF record, which I will add.
The SPF record is becoming more and more important, and while I'm not sure it's causing your exact problem, it definitely needs to be there.
Check this site for help in properly creating the SPF record: http://www.openspf.org/
What was your SOA expire set to??
Check this site for help in properly creating the SPF record: http://www.openspf.org/
What was your SOA expire set to??
Active today
SOA EXPIRE time is : 2592000 seconds, which was flagged as being too high. We submitted the change request to our ISP.
We've been running the ping test and periodically running the DNS reports for our domain dnscog.com and dnsstuff reports throughout the day. Although we get a pretty consistent ping reply, one of our three nameservers occassionally is not reponding. The other two have been up consistently. We've contacted our ISP to investigate.
If a sender was attempting to get our MX record and one namesserver was down, wouldn't it go to one of the other two to get the record (if it didn't have it?)
We've been running the ping test and periodically running the DNS reports for our domain dnscog.com and dnsstuff reports throughout the day. Although we get a pretty consistent ping reply, one of our three nameservers occassionally is not reponding. The other two have been up consistently. We've contacted our ISP to investigate.
If a sender was attempting to get our MX record and one namesserver was down, wouldn't it go to one of the other two to get the record (if it didn't have it?)
Featured Post
Need expert help—fast? Use the Help Bell for personalized assistance getting answers to your important questions.
Question has a verified solution.
Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.
Have a better answer? Share it in a comment.
Join & Write a Comment Already a member? Login.
This article explains how to move an Exchange 2013/2016 mailbox database and logs to a different drive.
In a Cross Forest, the steps to migrate users are quite complicated and even in the official articles of Technet there is no clear recommendation on which approach to take .. From an experience, I mention and simplify which way to go and how to use …
In this video we show how to create a mailbox database in Exchange 2013. We show this process by using the Exchange Admin Center.
Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center.
Navigate to the Servers >> Data…
In this Micro Video tutorial you will learn the basics about Database Availability Groups and How to configure one using a live Exchange Server Environment.
The video tutorial explains the basics of the Exchange server Database Availability grou…
Suggested Courses
Course of the Month7 days, 15 hours left to enroll
585 members asked questions and received personalized solutions in the past 7 days.
Join the community of 500,000 technology professionals and ask your questions.