Installing Message Queuing triggers
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2
Installing Message Queuing triggers
Message Queuing Triggers is an integral part of Message Queuing and can be installed during Message Queuing Setup by selecting the Triggers subcomponent. Triggers and rules are defined and managed in the Computer Management snap-in. Diagnostic data generated by the Message Queuing Triggers service are recorded in the Application Log and can be viewed using Event Viewer.
The support for Message Queuing Triggers can be installed by Message Queuing Setup during the installation of a Message Queuing server or independent client on computers running platforms from the Windows Server 2003 family. Message Queuing Triggers cannot be installed on a dependent client.
To install Message Queuing Triggers, select the Triggers subcomponent of Message Queuing during the installation of a Message Queuing server or an independent client. If the check box for this subcomponent is selected, the Triggers service is installed automatically and started. If this check box is not selected, the Triggers service can be installed later by running Add or Remove Programs and selecting Triggers in the Windows Components Wizard.
An answer file for unattended setup can contain an msmq_TriggersService = ON entry, which corresponds to selecting the Triggers check box on the Message Queuing page of the Windows Components Wizard.
Setup requires the presence of four files for the Triggers service in the \Windows\System32 folder: mqtrig.dll, mqtgsvc.exe, mqgentr.dll, and mqtgclus.dll.
By default, the Message Queuing Triggers service runs under the Network Service account. Services that are running under this account interact with the network using the credentials of the computer account, and this account has the same level of access to resources and objects as members of the Users group accounts. For heightened security, you can change the default Triggers service account to a more secure setting; for example, the Local Service account, which limits access to the local computer. You can also specify a less secure account for the Triggers service; for example, the Local System account, allowing access to the entire domain. Note that the Triggers service running under the Network Service account does not interact with the desktop. If this functionality is required, you can configure the Triggers service to run under the Local System account, and enable interaction with the desktop in Computer Management.
Message Queuing Triggers installs with a set of default configuration values that are stored in the registry. These values can be changed later using the Computer Management snap-in. For more information on how to change the default configuration, see Change default configuration values for triggers.
Message Queuing Triggers is cluster-aware and supports the active/active model. When the Message Queuing service fails over to another node, the Triggers service can fail over along with it. For this to occur, you must create a Message Queuing Triggers resource with resource dependencies on the Message Queuing resource and the Cluster Name resource on the applicable node using Cluster Administrator, and you must bring it online. The trigger and rule definitions for the cluster resource are stored in the local Windows registry. The Message Queuing Triggers resource is checkpointed with this registry key and the subkeys under it so that when the resource is moved to a new node (during failover, for example), the required keys propagate to the local registry on the new node. After failover, the Triggers service can thus continue to process the incoming messages in each monitored queue and invoke the applicable stand-alone executable or COM component according to the rules defined. For more information on server clusters and the active/active model, see Distributing Message Queuing in a network. For more information on creating and configuring Message Queuing Triggers resources in a virtual server, see Configure trigger resources for server clusters.