Solved

Implementing DAG in two site configuration

Posted on 2010-11-11
7
1,850 Views
Last Modified: 2012-05-10
OK so we currently have 2 active sites (A&B) with an Exchange 2010 SP1 server at each site, with users accessing both and are looking to implement DAG's. We also have a 3rd site (C) that is used for hosting our spam appliances and intranet servers. All sites are connected via a WAN, in the same AD domain and each site is in it's own AD Site.

My main concern with implementing DAG's in this configuration is what happens if I lose WAN connectivity?

I've read that SP1 now supports this type of configuration and helps prevent the potential 'split-brain' situation through the use of DAC (Datacenter Activation Coordination)

I have questions though.

Where should I place my primary FSW?
Should I configure an Alternate FileShareWitness server?

Example: Could I have Site A + FSW and Site B + AltFSW? What would happen if I lost WAN connectivity?

In the future we plan to implement a 4th site with an Exchange server.
0
Comment
Question by:Jaws03
  • 4
  • 3
7 Comments
 
LVL 49

Expert Comment

by:Akhater
ID: 34118332
>> My main concern with implementing DAG's in this configuration is what happens if I lose WAN connectivity?

the site with no file share witness will go down due to loss of quorum

>> I've read that SP1 now supports this type of configuration and helps prevent the potential 'split-brain' situation through the use of DAC (Datacenter Activation Coordination)

it does but wan connectivity issues are still not supported

0
 

Author Comment

by:Jaws03
ID: 34139236
>> >> My main concern with implementing DAG's in this configuration is what happens if I lose WAN connectivity?

>>the site with no file share witness will go down due to loss of quorum


What would happen if I had an alternate file share witness at the other site?
0
 
LVL 49

Expert Comment

by:Akhater
ID: 34140549
the concept of the alternate share witness is totally different, it is used only one you do a datacenter failover it is not for these scenarios

0
Is Your AD Toolbox Looking More Like a Toybox?

Managing Active Directory can get complicated.  Often, the native tools for managing AD are just not up to the task.  The largest Active Directory installations in the world have relied on one tool to manage their day-to-day administration tasks: Hyena. Start your trial today.

 

Author Comment

by:Jaws03
ID: 34141079
So if WAN connectivity is lost all the users at the site with no FSW will not be able to access email even thought they have a functioning email server in the same location as them? Seems kind of limited?
0
 
LVL 49

Accepted Solution

by:
Akhater earned 500 total points
ID: 34141099
>> So if WAN connectivity is lost all the users at the site with no FSW will not be able to access email even thought they have a functioning email server in the same location as them?

exactly

>> Seems kind of limited?

DAG cross site was designed to be in a DR site as active/passive model and not as active/active. It could be better I know, hopefully exchange 2013 :)
0
 

Author Closing Comment

by:Jaws03
ID: 34149846
NO
0
 
LVL 49

Expert Comment

by:Akhater
ID: 34152820
@Jaws03 I am sorry but what do you mean by "NO" and why was this graded a B ? what was wrong in my answer ?
0

Featured Post

Best Practices: Disaster Recovery Testing

Besides backup, any IT division should have a disaster recovery plan. You will find a few tips below relating to the development of such a plan and to what issues one should pay special attention in the course of backup planning.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article lists the top 5 free OST to PST Converter Tools. These tools save a lot of time for users when they want to convert OST to PST after their exchange server is no longer available or some other critical issue with exchange server or impor…
Read this checklist to learn more about the 15 things you should never include in an email signature.
To show how to create a transport rule in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: First we need to log into the Exchange Admin Center. Navigate to the Mail Flow >> Rules tab.:  To cr…
This video demonstrates how to sync Microsoft Exchange Public Folders with smartphones using CodeTwo Exchange Sync and Exchange ActiveSync. To learn more about CodeTwo Exchange Sync and download the free trial, go to: http://www.codetwo.com/excha…

776 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question