Hi All, we have existing domain controller 2008 like ALK.com and all users and our applications are connected with DC and we dont want to disturb existing DC, users and applications which are connected with our domain. Now we are going to install exchange server 2010 and want to know that can we install exchange 2010 on additional domain controller? what will happen if we restart our DC due to any reason will it affect on our mails, will our emails stop responding or not? how can i minimize the down time? Thanks, Ali.

It is not recommended to install exchange 2010 on domain controller due to security and perf reaosns. however technically u can do it. regarding restart dc and mail flow issues. If you have only one exchange box, yes ur mail flow will be affected. However, incomng external emails will try to retry to send emails again though. but you have high availability in exchange you can over come this issue. Thanks Uday Kiran, Senior Consultant Cyquent Technology Consultants, Dubai Please Mark as answer if it helps you

@ Uday "but you have high availability in exchange you can over come this issue." You can't use HA if you have exchange installed on Domain Controller, it has to be on Member server. If you have multiple DC's than it's not going to affect anything, It's strongly recommended to not to install Exchange 2010. There are so many reasons to not to install the server on Domain Controller. Cheers,Gulab | MCITP: Exchange 2010-2007 | Skype: Gulab.Mallah | Blog: www.ExchangeRanger.Blogspot.com

Hi Gulab, Appreciate your feedback :) I also believe that it is recommended to install High Availability ex2010 on member server. But if you see exchange 2010 (standalone) can be installed technically. same way i do not see any issue in installing high availability like CAS NLB and DAG on domain controller. Technically its possible but not recommendedThanks Uday Kiran, Senior Consultant Cyquent Technology Consultants, Dubai Please Mark as answer if it helps you

You can have HA (DAG) on Member server only. No, you can't have DAG Member server on Domain Controller. http://smtp25.blogspot.com/2008/11/why-we-should-not-install-exchange-on.html Gulab | MCITP: Exchange 2010-2007 | Skype: Gulab.Mallah | Blog: www.ExchangeRanger.Blogspot.com

Thanks all of you. it means if i dont want to disturb my exisiting domain controller then i need to make another domain controller and i can install exchange 2010 on member server of that new DC. existing DC will use for Local (users/apps) 2nd DC will be used for emails/exchange only what do you suggest? if someone can share the HA DAG document with me i want HA for exchange. can i install exchanage with DAG on virtual machines using Hyper-V is it recommended

hi, you can specify special dc to use exchange server 2010. here is detailed DAG article series; http://www.msexchange.org/articles_tutorials/exchange-server-2010/high-availability-recovery/uncovering-exchange-2010-database-availability-groups-dags-part1.html http://blogs.msexchange.org/walther/2009/04/18/exchange-2010-database-availability-groups/ http://technet.microsoft.com/en-us/library/dd979799.aspx regards, Mumin CICEK | www.cozumpark.com | Please click Vote As Helpful if it is helpful for you and Propose as Answer!!!

I find my self in this boat now, I have a customer that installed Exchange 2010 on a 2008 R2 DC. is it true you CANT do DAG? Is there any official post on microsoft listing out WHY you cant do this? Trust, me, i know it's a HORRIBLE idea but I need something to reference for the customer. What other issues can they expect to see or potentially see in doing this configuration?Thanks, Grady Vogt