installing different domain into an existing domain

You don't need to create a new AD Domain just to install Exchange - install it into your existing AD domain (wfcu.local) and you will be fine.

You can accept mail for multiple external domain names, irrespective of the internal domain name.

So, in your case, you want to add the Domain Controller to the existing forest.

But - is the Windows 2008 R2 server you are installing going to be used for Exchange 2010?  If it is - DO NOT make it a Domain Controller - it is not necessary and is a security risk.

Alan

yes it is a 2010 exchange

the reason I ask, is that when I try to install the exchange I get, “can't find active directory”, even though the computer itself is part of wfcu.local and I logon as an administrator of wfcu.local

if I do NLTest.exe /DsGetSite the reponse is : Getting DC name failed status=1919 0x77f Error_No_Sitename

so here is what i have:
inside:
mail.whitefishcu.com   192.168.2.212 in dns
new 2020 r2 is called windows-exch.wfcu.local in dns
outside:
mail.whitefishcu.com  50.50.50.6 (just an example)

I get a question is server internet facing:
Given the info above is it or not.  I am guessing not.  Even though there is a rule that passes email between the outside and the inside through the firewall.

No matter what I check on the install, exchange tells me that it can not find an active directory when it trying to do the hub transport part.   If it is the whitefishcu.com then I figured I needed to add the second domain.  If not what is it looking for??????

gary

What have you configured in the LAN adapter on the soon to beExchange server for DNS?  It should be pointing to your Domain Controller if that has DNS configured as a service on it, nothing else.

it does, only

working my way through prerequisites will let you know by monday what is happening.

gary

No problems - sounds like you have yourself a fun weekend ahead ; )