This document describes a problem encountered with Load Balancers and the Cisco Unity Connection Single Inbox feature. Often this issue is caused when the Sticky Connection feature is not used. Essentially, you want the same Exchange Web Service (EWS) connection used throughout the same transaction. This document provides a specific example of an issue seen with a Load Balancer in use.
Messages for different users do not consistenly sync to Microsoft Exchange 2010. This means that there are times when messages for the same users sync properly without any change.
In the case described here, a Cisco Application Control Engine (ACE) Hardware Load Balancer is in use. The CuMbxSync trace might show this error at the moment of failure:
HTTP request failed with error:
Failed sending data to the peer --
SSL read: error:00000000:lib(0):func(0):
reason(0), errno 104, HTTP status code: 0
A packet capture might indicate an EWS connection from Cisco Unity Connection to Microsoft Exchange that resets. The reset might be caused by the Load Balancer.
The Load Balancer uses a policy that is designed for Microsoft Outlook Web Application (OWA), and it resets connections frequently. In order to resolve the issue, you must create another virtual IP on the Load Balancer that is also used in order to connect to the Microsoft Exchange Client Access Server (CAS), but is not processed through the OWA policy that applies the Sticky Connection based on session cookies. Then, point Cisco Unity Connection Unified Messaging Service to this virtual IP address, and apply it to the user.
In order to implement this solution, complete these steps:
Revision | Publish Date | Comments |
---|---|---|
1.0 |
04-Sep-2013 |
Initial Release |