The Unified Messaging server did not receive an incoming call because a Hub Transport server is currently busy or not available
Topic Last Modified: 2007-11-16
The Microsoft Exchange Server 2007 Management Pack for Microsoft Operations Manager (MOM) monitors the Windows Application log on computers that are running Exchange Server 2007 and generates this alert when the event or events specified in the following Details table are logged.
To learn more about this event, do one or more of the following:
Review the description of the event that includes the variables specific to your environment. From the MOM Operator Console, select this alert, and then click the Properties tab.
Review all events that have been logged that meet the criteria of this MOM alert. From the MOM Operator Console, click the Events tab, and then double-click the event in the list for which you want to review the event description.
Details
Product Name |
Exchange |
Product Version |
8.0 (Exchange Server 2007) |
Event ID |
1081 |
Event Source |
MSExchange Unified Messaging |
Alert Type |
Warning |
MOM Rule Path |
Microsoft Exchange Server/Exchange 2007/Unified Messaging |
MOM Rule Name |
The Unified Messaging server did not receive an incoming call because a Hub Transport server is currently busy or not available. For more information, see the event description. |
Explanation
This Warning event indicates that the computer that has the Unified Messaging server role installed was not able to accept any new voice or fax messages destined for the user referenced in the event description. The Unified Messaging (UM) server may respond to the request with message that resembles "Sorry, we can't take the message right now. Please call back later" before the call is disconnected. By default this warning is logged when there are more than 1,000 message requests pending for the Hub Transport server. Another symptom you may experience when this event occurs is that MSExchange Unified Messaging Event ID 1082 is logged in the Application log.
Event ID 1081 may be caused by one or more of the following:
The computer that is running the Hub Transport server role may be too busy processing the message requests submitted by the UM server.
A computer that is running the Hub Transport server role cannot be found in the same Active Directory® site as the UM server. The two server roles must be installed in the same Active Directory site.
The Microsoft® Exchange Transport Service installed at the Hub Transport server is not running.
An SMTP receive connector is not created or configured correctly at the Hub Transport server.
User Action
To resolve this warning, do one or more of the following:
If you frequently receive this warning because of a high volume of voice or fax messages, or a high workload at the Hub Transport server, consider adding another Hub Transport server in the same Active Directory site to load balance the requests submitted by the UM server.
Make sure that there is at least one Hub Transport server installed in the same Active Directory site as the UM server.
Make sure that the Microsoft Exchange Transport service is enabled and running on the Hub Transport server.
Make sure than an SMTP receive connector is created on the Hub Transport server. Consider the following when you configure the SMTP receive connector:
It should be configured to accept messages from the UM server.
It should be configured to use at least Transport Layer Security (TLS).
It should have Exchange Server Authentication enabled.
Enable SMTP protocol logging to troubleshoot SMTP transport issues. SMTP protocol logging can log the SMTP protocol conversation when UM server submits messages to the Hub Transport server over the SMTP protocol. For more information about SMTP protocol logging, see How to Configure SMTP Protocol Logging.
For more information about the UM message flow, see Overview of the Unified Messaging Message Flow, and Understanding Unified Messaging Incoming Call Handling.
For more information about load balancing and high availability, see High Availability.
For More Information
To search the Microsoft Knowledge Base articles based on criteria that generated this alert, visit the Search the Support Knowledge Base (KB) Web site.
To review Exchange 2007 event message articles that may not be represented by Exchange 2007 MOM alerts, see the Events and Errors Message Center.
If you are not already doing so, consider running the tools that Microsoft Exchange offers to help administrators analyze and troubleshoot their Exchange environment. These tools can help you make sure that your configuration is in line with Microsoft best practices. They can also help you identify and resolve performance issues, improve mail flow, and better manage disaster recovery scenarios. Go to the Toolbox node of the Exchange Management Console to run these tools now. For more information about these tools, see Toolbox in the Exchange Server 2007 Help.