Kindly need your support as I am facing a serious issue. I am working on Exchange migration project , the below is the case:

-          I have Exchange 2010 with SP3 , 3 nodes in 3 branches.

-          Every node has its own DB which belong to this branch.

-          I installed 4 SRV with windows server 2012 R2.

-          I deployed Exchange 2013 on these 4 servers ( 2 MB & 2 CAS).

-          I created windows NLB for 2 CAS servers . It has been tested successfully.

-          I created DAG between 2 MB servers.

The issue is when MB01 is down , I cant logon through OWA or ECP although DB is switched to MB02 successfully and users still connected using outlook and they can send receive normally .i tried to remove MB02 & reinstall it again with the same issue.

I can login only when MB01 down on ECP using the link : https://mail.domain.com\ecp\exchclientver=15. But still not be able to login to OWA.

Is that because the environment still has Exchange 2010 ? or what could be the issue?

Kindly to help .

When deploying a coexistence scenario, before moving any mailboxes you should ensure that all CAS functions go through the Exchange 2013 servers.

You have not tested the service work without Windows NLB.
Windows NLB is not recommended for Exchange 2013.

NLB is supported with Exchange 2013 although HLB or VHLB are better options.

Hi,

Is there any error when you access the OWA? Can you access the OWA with the following URL in CAS01 and CAS02?

Https://localhost/owa

Please check your OWA configuration in your two CAS servers:

Get-OwaVirtualDirectory | FL Identity,*Authentication*,*url*

Regards,

Thanks All for your response.

The issue has been solved. It was my mistake as I added the admin mailbox in defualt DB for MB01. now I moved ithis Mailbox and everything going good. :) 

Again, Thanks All for your kindly support.

• Marked as answer by Magdy911 20 hours 39 minutes ago