Recently, I added additional CPU's to the CAS servers, and in general, CPU utilization has been lowered which is great.  But in our environment, we have a handful of 3rd party service accounts that has to access the Exchange system.  When running the Exchange Troubleshooting tool, it's always a combination of service accounts and random mailboxes that have MAPI/RPC issues.

Since I added additional CPU's on the CAS servers and even on mailbox servers, is it possible to configure MAPI/RPC operations to take advantage of the additional CPU's?

As a side note, we are 99% Outlook online mode vs cache mode since our desktops VDI images. 

Thanks

Ron

I don't think so you will be able to specify additional CPu's to use specifically only MAPI/RPC 's 

Sathish,

If I can't configure MAPI/RPC to take advantage of more CPU's on a CAS server, will adding another CAS server help to the CAS array?

Currently, I have 400 Outlook 2010 online users connecting to a casarray (two CAS servers).  Will adding a 3rd CAS server help reduce the impact of any MAPI/RPC connections?

Thanks

Ron

Sathish,

On our desktop, we also have the Lync 2013 client running.  Can Lync impact Outlook performance/responsiveness?

I installed Fiddler, and I see Lync tunneling to the casarray more than I do Outlook.

Thanks

Ron

Hi Ron,

As we know, MAPI connections are handled by the Client Access server in Exchange 2010.The RPC Client Access service provides data access through a single, common path of the Client Access server, with the exception of public folder requests, which are still made directly to the Mailbox server.

It means more CAS server, there will be fewer connectivity performance issues

So, if adding more CAS server to CAS Array will help reducing the impact of any MAPI/RPC connections.

Best regards,

Thanks Niko.

I'll give it a shot.

Ron

Hello,

Addition to Niko's suggestions, I would recommend to use multi-role servers and use a Load balancer. there are many low cost load balancers in the market.

With that design, you can use additional CPU and memory across the all exchange roles.

Regards

Thanks for your response Chinthaka.

We are taking advantage of our Citrix Netscaler to load balance connections to the CAS servers.

Ron

Hi TrojansBaby, please check out Log Parser Studio. It is available here http://blogs.technet.com/b/exchange/archive/2013/06/17/log-parser-studio-2-2-is-now-available.aspx.

This tool will allow you to analyze log files for RPC and MAPI connections in your exchange environment and can help narrow down the problem users that may be using more resources than they should. I used this tool to address EAS users who were accessing more CPU than other users when synching contacts on their mobile devices and to address that I created custom throttling policies for those users.

Thanks

I'll check it out.

Ron

Ron,

Where you able to resolve this?

With everyone's responses. I'm moving in the right direction. In terms of Log Parser Studio, I need to install .net 4.x so I'll need to schedule the install during a maintenance window.     I'm looking forward to this.

Also, we updated one of our 3rd party vendor solutions.  This 3rd party solution was using MAPI to access the Exchange DB's, and the update allowed us to use Exchange Web Services (It took a while for the vendor to go this route.).  It has improved things.

Thanks

Ron