Hello,

I have two combined exchange 2013 SP1 servers fresh installation. Both are DAG configured. We dont have load balancer for CAS. I simply created A record webmail.abc.com in internal DNS and pointed to one Exchange Server and all the virtual directories have same internal and external link webmail.abc.com I am facing problem, dont know whether is related to virtual directories or no. I can move the 4 databases from one server to another manually. Now if all the databases are mounted on server02, I can access owa and ecp without any problem from both the servers. The problem comes when I restart server02, all the databases are successfully mounting on server01 but my weblinks dont work especially ECP. Sometime owa works and sometime it doesnt. everything becomes normal when I fail back to server02 by restarting server01. The below warning is logging in application eventviewer;

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Log Name: Application
Source ASP.Net 4.0.30319.0
Event ID 1309
Event code: 3005
Event message: An unhandled exception has occurred.
Event time: 3/5/2015 3:52:14 PM
Event time (UTC): 3/5/2015 12:52:14 PM
Event ID: a16f4f24856649ee85de801facd9a679
Event sequence: 245
Event occurrence: 36
Event detail code: 0
 
Application information:
    Application domain: /LM/W3SVC/2/ROOT/owa-1-130700320948602486
    Trust level: Full
    Application Virtual Path: /owa
    Application Path: D:\Microsoft\Exchange Server\V15\ClientAccess\owa\
    Machine name: server02

---------------------------------------------

I recreated ecp virtual directory by following the below link but no use

https://unifiedit.wordpress.com/2014/04/22/exchange-2013-sp1-unable-to-log-on-to-ecp-asp-net-4-0-30319-0-unhandled-exception/

I spent the whole day to diagnose the issue but could not. Please advise..

You need to implement some sort of load balancing (or separate namespaces between CAS Servers) because right now DNS resolves your namespace to the CAS that is down.

Take a look at this blog regarding load balancing options with 2013.

http://blogs.technet.com/b/exchange/archive/2014/03/05/load-balancing-in-exchange-2013.aspx

Thanks for reply. we have only two servers with combined roles. cannot configure load balancing because both the servers are in DAG. Kindly explain what is meant by 'separate namespaces between CAS servers'.

You can still configure load balancing, you just cant configure the servers in the DAG to host a Windows NLB cluster (which is good, b\c no one i know likes them).  There are alot of other solutions, like a hardware load balancer or DNS Round Robin that you can deploy here to make your life easier.  All of the pros and cons of each solution is outlined in that article. 

What I mean by different namespaces is this:

Server1 uses mail1.domain.com for Outlook Anywhere, Autodiscover and all of it's virtual directories. 

Server2 uses mail2.domain.com for Outlook Anywhere, Autodiscover and all of it's virtual directories. 

Now this setup really isnt ideal, since users will need to know 2 different URLs depending what mail server their mailbox is on.  I would highly recommend looking into a hardware load balancer.  Then you can keep it hte way it is and point your mail.domain.com namespace to the Virtual IP on the load balancer.

The management is not interested to buy load balancer that why I could not deployed it. but it should work without load balancer. My problem is, owa and ecp links dont work when all the load comes on server01. there is no problem with server02 all the web links are working normally.

I thought there is a problem in Exchange IIS virtual directories. some thing is not going right. Can any please explain what exactly the virtual directories binding order looks like after Exchange Installation?

Thanks

• Edited by Sawag 14 hours 26 minutes ago

I thought there is a problem in Exchange IIS virtual directories. some thing is not going right. Can any please explain what exactly the virtual directories binding order looks like after Exchange Installation?

Thanks

• Edited by Sawag Saturday, March 07, 2015 4:51 PM

Kindly help me to resolve the issue. I am still facing the problem.

Hi,

Please try the following steps to solve this issue firstly

1. On the Exchange Server (CAS) go to directory \Exchange\ClientAccess\owa\15.0.516.30\owa2\ext\killbit
2. If the file killbit.xml is present and delete or cut it to other folder for backup.
3. Run iisreset.

If this doesnt work, please check if there any other events in application logs. Based on my knowledge,  this event is always accompanied with other events. And please post Exception information section in this event for us to diagnose this issue. Thanks for cooperation.

Best Regards.