Exchange Server 2013-DNS configuration

New Contributor

Hello Community,


I need help with setting up the correct DNS(internal/external) configuration:


I have setup Exchange server 2013 like this :


  1. 2 CAS vms (DAG with Cas1 as the witness)
  2. 2 MBX vms


  • in the internal DNS: I have two zones (the local lab.local and the external lab-**.com)
  1. lab.local =>I have added two "A" records that points the CAS 1 and CAS2  private IPs.
  2. Lab-**.com=> I have added Two "A" records that points both CASs private IPs and an autodiscover/mail/smpt "A" records that points CAS 1.


  • in the external DNS :I have created an "A" record that points the public IP of the CAS1 and a "CNAME" for autodicover that points "mail.lab-**.com" and an MX record that points "mail.lab-**.com" .


with this configuration I am not capable of sending nor receveiving emails (internally and externally) .


Thank you in advance.

1 Reply
emails withing the domaine works fine now but I am facing another challenge configuring the DAG:
As I sad the witness server is located within the CAS 1 server,but when I try to add the two MBX to the DAG it wont work (I have tried adding them seperatly /rebooting...nothing would work )

the error msg is :


A server-side database availability group administrative operation failed. Error The operation failed. CreateCluster errors may result from incorrectly configured static addresses. Error: An error occurred while attempting a cluster operation. Error: Cluster API failed: "CreateCluster() failed with 0x5b4. Error: This operation returned because the timeout period expired". [Server: Lab-EX-MBX1.lab.local]

for information the vms are located in Azure .

Thank you in advance.