Inter-Organization Replication Tool


Topic Last Modified: 2011-05-25

Released/Updated   July 2009

This topic describes the Inter-Organization Replication tool, which was first released as part of Microsoft Exchange Server 5.5 Service Pack 3 (SP3), with an updated version for Microsoft Exchange 2003. The tool is also compatible with Exchange Server 2007 and with Microsoft Exchange Server 2010 Service Pack 1 (SP1).

The Inter-Organization Replication tool is used to replicate free/busy information and public folder content between Exchange organizations. It enables the coordination of meetings, appointments, contacts, and public folder information between disjointed Exchange organizations.

The tool consists of two programs: the Replication Configuration program (Exscfg.exe) and the Replication service (Exssrv.exe). The Replication Configuration program creates a configuration file for setting the replication frequency, logging options, folders to be replicated, and accounts to be used. The Replication service uses a configuration file that is created by the Replication Configuration program to continuously update information from one server (designated as the Publisher) to one or more Exchange servers (designated as Subscribers).

Schedule+ free/busy information is replicated from Publisher to Subscriber only. Because of this, you must have two free/busy sessions to bidirectionally update free/busy information. Public folders can be replicated bidirectionally between Publisher and Subscriber. You can configure the replication frequency, the logging of message and folder replication, and how much processing power you want devoted to the replication process.

This topic includes the following information:

  • Multiple Exchange Organization Scenarios

  • Security

  • Deployment Phases

  • Planning

  • Preparation

  • Installation and Configuration

  • Testing

  • Planning Phase

  • Preparation Phase

  • Preparing the Publisher Server

  • Preparing the Subscriber Server

  • Adding Availability Address Space in an Exchange 2007 or Exchange 2010 Organization

  • Configuring Exchange 2007 or Exchange 2010 in a Single-Server Exchange Organization

  • Installation and Configuration Phase

  • System Requirements

  • Network Requirements

  • Installing the Inter-Organization Replication Tool

  • Running the Inter-Organization Replication Tool

  • How to Share Free/Busy Data Among More Than Two Exchange Organizations

  • Testing Phase

  • Common Issues
  • Multiple Exchange Organization Scenarios

    Multiple Exchange organizations can exist in an enterprise. Reasons to have multiple Exchange organizations include the following:

  • A merger with or acquisition of a company that has a separate Exchange organization occurs.

  • Servers are added to a different Exchange organization that may be merged with the parent organization.

  • Legacy versions of Exchange must share public folder and free/busy information with Exchange servers in different organizations.

  • Exchange servers are administered separately in different organizations because of geographical constraints.

  • A company has a business partner, and the two organizations agree to share information without actually moving their Exchange servers together in an Exchange organizational structure.

  • When an Exchange topology that includes two or more organizations exists, the Inter-Organization Replication tool can be used to replicate free/busy and public folder information.

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    The Inter-Organization Replication tool helps to bring about the sharing of intra-organizational public folder content while preventing direct remote access to your public folder system for users from a foreign Exchange organization. Sharing information between companies requires tight integration with network security and detailed management of replicated content. Each participating company should perform a detailed evaluation of their public folder environment to determine which public folders are appropriate for sharing with an external organization.

    The Inter-Organization Replication tool uses the security credentials of mailbox-enabled user accounts to authenticate to the public folder store from each participating organization. The logon credentials for these shared user accounts must be kept secure. Otherwise, there is potential for a security breach. The Inter-Organization Replication tool helps make sure that the privacy of shared information is maintained during replication. However, the burden of correctly securing the replicated data is the sole responsibility of the Exchange administrators in the Subscriber organization.

    Deployment Phases

    Deploying the Inter-Organization Replication tool in an Exchange environment typically involves the following phases.

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  • Determine which organization will host the Inter-Organization Replication service.

  • Determine which Exchange administrator will be responsible for creating configuration files.

  • Determine which type of data (public folder or free/busy content) has to be replicated.

  • To replicate free/busy information, determine how mail-enabled contacts will be created in each organization.

  • Determine replication direction (one-way or two-way) for the content.

  • Determine how to handle replication of permissions and deletion of content.

  • Preparation

  • Create mail-enabled contacts for each user in the partner organization.

  • Prepare the Publisher server.

  • Prepare the Subscriber server.

  • Add Availability Address Space for pure Exchange 2007 organizations with Office Outlook 2007 clients.

  • Configure Exchange 2007 in a single-server Exchange Organization.

  • Installation and Configuration

  • Meet system and network requirements for installing and running the Inter-Organization Replication tool.

  • Install the Inter-Organization Replication tool by using the correct service account.

  • Use the Configuration tool to create replication sessions for replicating content.

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  • Use Microsoft Outlook to send and accept meeting requests with users from the partner organization.

  • Wait for the replication interval to occur, and look for any replication errors.

  • Examine updated free/busy information for users in the partner organization.

  • For public folders, create new content, and then check the Subscriber organization after replication occurs.

  • Planning Phase

    Proper planning is critical for successful replication of public folder content or free/busy information between Exchange organizations. Before you install the Inter-Organization Replication tool, the Exchange administrators from each company should work together to develop a deployment plan that addresses the following questions:

  • Do you have to replicate free/busy information between the organizations?

  • Is replication of free/busy information needed for only one organization or both?

  • Is replication only for users in specific administrative groups (sites) or for all users?

  • How will you create mail-enabled contacts for every user of free/busy information in the other organization?

  • Do you have to replicate public folder content between the organizations?

  • Which public folders have to be replicated from each organization?

  • Will changes that are made to the replicated public folder content in the Subscriber organization be replicated back to the Publisher organization?

  • Do you replicate the deletion of folders or content to the Subscriber organization?

  • How will the replicated public folder data in the Subscriber organization be secured?

  • Which organization will be responsible for hosting the Inter-Organization Replication tool?

  • Who will be responsible for creating and maintaining the configuration files for replication sessions?

  • Will network traffic from the Inter-Organization Replication tool be inhibited by firewall devices?