Microsoft DNS, Sun Solaris, and Domain Alias

We recently made some additions to our DNS server to be locally authoritative for our domain.  After this change our Sun Solaris box could no longer email internally to our exchange server.  We figured out what the problem was, and a temporary fix, but it's just temporary.  Looking for a permanent fix.

before DNS changes the email showed up as (correct)
after DNS changes the email shows up as (incorrect, and only an issue with the Sun box)

we figured out that if we removed the domain alias (in Microsoft DNS) to translate to it worked again and the emails started going to

Ideas of how we can fix this permanently?
Who is Participating?

Improve company productivity with a Business Account.Sign Up

Cyclops3590Connect With a Mentor Commented:
how is the Sun box sending its email.  This just seems odd to me; the Sun box is email so something like, correct?  I guess I don't understand how your Sun box is set up for emailing or what daemon on that box is doing the emailing

also, if you are just doing CNAME entries, is there a reason that the can't be the A record and the be the CNAME entry; just reverse the two.
prashsaxConnect With a Mentor Commented:
Any specific reason that you want to have a www alias for your domain.

bschwartingAuthor Commented:
just so users that try to browse to will resolve to
What Kind of Coding Program is Right for You?

There are many ways to learn to code these days. From coding bootcamps like Flatiron School to online courses to totally free beginner resources. The best way to learn to code depends on many factors, but the most important one is you. See what course is best for you.

prashsaxConnect With a Mentor Commented:
So create ALIAS record with "www" only and point it towards the web server.

Now, you can type www only in browser and its FQDN would be

It would open web server default site either with www or
bschwartingAuthor Commented:
i figured it out.  i made them both an A record and it worked.  they both resolve correctly now.

any reason i should do this?
bschwartingAuthor Commented:
sorry, any reason i shouldn't do this.
prashsaxConnect With a Mentor Commented:
I don't think of any reason why not, but I would have done the other way to access website.

Good, if this works for you. :-)
>sorry, any reason i shouldn't do this.

I don't think there's a reason, but the way you were doing it originally was definitely broken - you are allowed (per RFC) to have a CNAME for www pointing to your domain name, but not the other way around.

Of course, Microsoft GUIs love to let you do things that violate RFCs - otherwise, they wouldn't be Microsoft, would they?

bschwartingAuthor Commented:
thanks for the help guys, split points to all.

answer accepted on Cyclops3590 because he got me thinking along the lines when he said, "is there a reason that the can't be the A record and the be the CNAME entry; just reverse the two."

i just used the 1st part.
bschwartingAuthor Commented:

I'm sure you are correct, per RFC, but I'm curious...

Why would I need a CNAME for a www record that is already covered in an A record?

Side Note:  Yes, just like Microsoft :)
CNAME is short for conical (sp?) name
A records associate an fqdn with an IP
CNAME creates an alias for an fqdn
example   A CNAME CNAME

This way if you run virtual hosts on your web server (meaning serve out different pages depending upon url used to connect to it) you can take advantage of the CNAME entries.  Also, if you need to change the IP of the web server (that hosts all the urls) then you only need to change one entry.
bschwartingAuthor Commented:
good explanation, thanks!
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.

All Courses

From novice to tech pro — start learning today.