Exchange server 2013 DAG and CAS load balance configuration

@suriyaehnop... he has ONE CAS server at each site, your links are for mulitple CAS in one site.

@rigelnet... Are you wanting to LB across sites? Is there a reason you want to do it this way?

Yes we have two sites but the domain name is same and both are connected with each other. Our scnario is as below

site 1 Servers

CAS1  
MAIL1  
MAIL2  
DC1  
 
site 2 Servers

CAS2
MAIL3  
MAIL4  
DC2  

we have configured mail.exch.com for the one site. we want to configure the same url for the both site so that we can get failover and load balance.

we have follow the above link to resolve the issue.
http://exchangeserverpro.com/exchange-2013-client-access-server-high-availability/

We have added A record in DNS of  Both site and as a result we are able to resolve mail.exch.com with both IP of both sites.

But with the above configuration our 1st site users are not able to connect outlook.

Autodiscovery isn’t working when users attempt to login now.

I believe it has something to do with the CAS server in site2. I removed the second DNS entry for mail.exch.com that points to the site2 cas and everyone is now able to get in.

What is the result of this command?

Get-ClientAccessArray

You have to Load Balance but since you have DAG you cannot use WCS, you will have to put a hardware load balancer (HLB) to manage the client access.

When we run command : " Get-ClientAccessArray" nothing is appear kindly find the screenshot.

Can you share step by step process on same hardware load balancer (HLB)
Capture.PNG

The problem you face is that you can only create one CAS array per site. You have multiple sites so you will not be able to load balance between them as they are on different subnets (I am assuming this but I doubt you will span one subnet across a WAN).

What you want to do for high availability is to setup 2 CAS servers per site and provide true LB for each site during a disaster or failover scenario.

For Hardware Load balancing, there are various flavors of load balancers and blogs to guide you. Here is one you can follow and they use KEMP LB's.

http://blogs.technet.com/b/ucedsg/archive/2009/12/06/how-to-setup-an-exchange-2010-cas-array-to-load-balance-mapi.aspx

I personally use Barracuda LB's but it all depends on a variety of factors and amount of users, traffic, etc..

Thanks for your help. thankyou