Hi,

I would like to find out for Exchange On Premises with EOP setup for belows:

1)  If Exchange 2010 existing domain has autodiscover CNAME to autodiscover.outlook.com.
     What is the best way to go about for new Exchange 2013?

2) Although CNAME for autodiscover no needed as told in Exchange on Premise setup, is there any advantage to maintain such?

3) Do the CNAME autodiscover will switch to new Exchange 2013 in the co-exist environment Exchange 2010 and Exchange 2013?

4) Should we remove the CNAME instead? 

• Moved by Jason Johnston [MSFT]Microsoft employee 17 hours 3 minutes ago Not a development question.

Hi CJohn,

As per my understanding EOP (Exchange Online Protection) doesn't come into picture for client connectivity, including Autodiscover to be specific.

Follow the Exchange Deployment Assitant which would provide you step by step guidance how and when to change it.

To answer your questions in short

1) Point the internal\external autodiscover.outlook.com to Ex2013 servers. Ex2013 will take control and automatically proxy or redirect the incoming requests as required to Ex2010

2)I don't quite get it, what you mean here, autodiscover is very much required for Ex2013 as well. There are various levels or options I would say that needs to be setup apart from only the CNAME part.

3)No, it will not automatically switch, you need to update it as per the migration guide I mentioned earlier. Make changes on the Ex2010 servers as well

4)No, don't remove point it to Ex2013

Moreover I can see its recommended to use Host records(A) instead of CNAME record for the autodiscover.domain.com

https://community.office365.com/en-us/f/156/t/175843

As on premise Exchange autodiscover cname to autodiscover.outlook.com.

Can anyone share how the record help to direct to Exchange on premise autodiscover xml file?

If I in the phases with 2 version Exchange at same enviroment, how do we ensure the autodiscover.outlook.com point to correct version of Exchange?

Hi John,

"I think the document you are seeing is for EOP+office365, if you have standard EOP license or not going to use office 365, you should be ok without changing autodiscoverer record."

As already mentioned on the other article, CNAME record- autodiscover.mycompany.com-autodiscover.outlook.com  on your Public DNS is not required for just EOP, even this is the case for some Hybrid installations of Ex2013.

The screenshot says 'Exchange Online' = O365, so what it appears that even if its only for EOP, the DNS verification mechanism page is common and hence requires you need to have it.

"I followed the lead of the related thread poster, and set up the autodiscover for long enough to complete the setup and verification process for each domain, then removed it."-Forum user

Autodiscover CNAME record In scenarios where all user mailboxes have been moved to Exchange Online, we can switch the autodiscover record to point directly to Exchange Online instead of at the on-premises Exchange organization. In our case, we will have user mailboxes in both Exchange Online and the on-premises Exchange organization over a period (which is the case in most scenarios that involve an Exchange hybrid), so were not interested in pointing the autodiscover record at Exchange Online as that would break autodiscover lookups for on-premises user mailboxes. Said in another way, we will skip this step. If we wanted to point autodiscover to Exchange Online, we would need to direct autodiscover.mycompany.com to autodiscover.outlook.com using a CNAME record.

References:

Configuring an Exchange 2013 Hybrid Deployment

http://www.msexchange.org/articles-tutorials/office-365/exchange-online/configuring-exchange-2013-hybrid-deployment-and-migrating-office-365-exchange-online-part12.html

Setting up Exchange Online Protection for Standalone environment

https://community.office365.com/en-us/f/156/t/178481