MX failed lookup and BIND

[M. Meadows]

We're seeing email failures to outlook.uga.edu. 
dig uga.edu +nssearch shows only dns3.uga.edu responds with an soa record.

and 
dig -t mx outlook.uga.edu @dns3.uga.edu returns an mx record.
outlook.uga.edu.        86400   IN      MX      10 707341637.mail.outlook.com.



And we see a problem with the uga.edu nameservers when attempting to get an MX record. 
3 of the 4 nameservers don't seem to be communicating with the world ... but one, dns3, is.
 

There are 4 name servers defined as authorities for uga.edu.


 

dns1.uga.edu.

dns2.uga.edu.

dns3.uga.edu.

dns4.uga.edu.

 It has been suggested that an AD server is consistently getting correct answers ... ie, is cycling through all 4 nameservers and coming up with the mx record ... but BIND servers are not consistently getting an answer. 
Confused about this. I believe I've read that resolv.conf will only take the 1st 3 nameservers in a search list ... but doubt that's really related to this issue.Guessing that during a recursive search that goes through the TLD nameservers info about all 4 of the uga.edu nameservers is passed along to whatever recursive server is performing the query. Then I would expect that server to try all the nameservers in the list. In fact, a test I've run seems to confirm this. Can anyone offer any other thoughts on this? Any reason this MX record check might fail on BIND servers? Obviously the fact that 4 nameservers are delegated authority for the domain and only 1 of them can be reached is an issue.





 Thanks,
Marty




 


 		 	   		   		 	   		  
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