Reference Materials for Migration 8.15 - Tips and Tricks

Considerations for Exchange Migration

Synchronization Agents

Agent File Locations and Disk Space

Agents should usually be installed on the drive with the maximum free disk space available. Each server can have only one location for all Exchange Migration Wizard agents. Changing this location requires agent reinstallation and job reconfiguration, so plan carefully before installing agents.

Each server allows you to specify the amount of free disk space required for the agents to run. You can specify a percentage of the total disk space or a particular size. Use whatever setting you are comfortable with, but it is best to stay on the safe side and make sure at least 500 MB of free space exists on all servers.

The mail and public folder agents use temporary PST files to transfer data and a database for a local cache. Substantial temporary disk space may be required, depending on the settings used.

Each agent has a log file associated with it. Use each agent’s option to specify the size at which the log will be archived and compressed.

Pre-installing the Agents on Exchange Servers

In large distributed networks with sites connected by slow links, Exchange agent deployment from Migration Manager for Exchange console may take up all available bandwidth. This happens because the Migration Manager for Exchange has to transfer the agent setup packages to the remote server before it can start installation. The shared components setup is about 15 MB and can take considerable time and bandwidth to be transferred.

Migration Manager for Exchange includes the files necessary for creating the installation package to install the Exchange agents on remote Exchange servers. The package can be distributed to remote sites on any removable media and local site administrators can perform installation prior to starting the migration process. The package setup creates all necessary folders and shares on servers and copies files to required locations.

Before installing the agents, make sure that all servers in your environment meet the software requirements listed in the Quest Migration Manager—System Requirements and Access Rights document.

The following files are located in the Migration Manager installation folder on the console computer:

• makepack.cmd – Creates the installation package on the console computer
• clnsetup.cmd – Setup file for cluster servers
• srvsetup.cmd – Setup file for non-cluster servers
• ccrsetup.cmd – Setup file for Exchange 2007 CCR cluster servers

These batch files allow you to create an installation package that can be then distributed to remote locations without consuming network bandwidth.

These files do not eliminate the need to run the agent installation procedure from the Migration Manager console. They simply allow the copying of the setup files to the required location in advance. After the files are copied, you need to finish the agent installation from the console.

Using Agent Hosts for Synchronization Agents

By default, the best migration performance is achieved when Migration Manager for Exchange agents are installed on the same Exchange servers as the mailboxes and public folders they process. However, in some cases, the only way to perform data migration successfully is to use an agent host for the Exchange server.

An agent host is a server that performs a role of substituted Exchange server in migration process. An agent host can be either an Exchange server or any other server. Single instances of all Migration Manager for Exchange agents are installed on that server (including the Public Folder Source Agent, Public Folder Target Agent, Mail Source Agent, Mail Target Agent, Mail Transmission Agent, Calendar Synchronization Agent, and Free/Busy Synchronization Agent).

Using agent hosts can be recommended in the following cases:

• If no additional software (i.e., Migration Manager for Exchange agents) should be installed on the production Exchange servers due to specific reasons
• If Migration Manager for Exchange agents installed on a particular Exchange server do not work correctly due to conflicts with the third-part software installed on that server

Before you start using agent hosts, consider the following:

• The following computers cannot be used as agent hosts:
  • Microsoft Cluster Servers (MSCS)
  • Microsoft Cluster Server nodes
  • Exchange Virtual Server
  • Exchange 2000/2003/2007 SCC clusters
  • Exchange 2007 CCR clusters
• If agent host is used, network traffic increases and migration slows down if compared to usual migration scenario. This happens due to additional mail transfer (from source Exchange server to agent host and from agent host to target Exchange server).
• To increase the performance and speed up migration process, it is recommended to use the agent host located in the same network segment as the corresponding Exchange server.
• One agent host can work with several Exchange servers, in particular, be an agent host for both a source and a target Exchange server at a time. However, in this case, the agent will process all assigned jobs sequentially, one after another, which may lead to performance degradation.
• Using agent host can be recommended for Exchange 2007 CCR to prevent problems with unexpected failover, as well as to solve problems with replication of data from the active to the passive node of the CCR cluster server (if they exist).

Directory Synchronization

When you configure the directory synchronization job, you specify the target administrative group and the information store in which the Directory Synchronization Agent will create mailboxes. These mailboxes can later be moved by the Mail Target Agent (MTA) or Calendar Synchronization Agent (CSA) to another information store or administrative group, as specified in the mailbox or calendar synchronization job.

However, it is recommended that you plan the initial mailbox creation during directory synchronization in a way that minimizes unnecessary mailbox moves across administrative groups by the mail and calendar synchronization agents.

Note that mailbox move from one administrative group to another is only possible if the Exchange organization is running in native mode.

Public Folder Synchronization

The following are the important issues to consider when synchronizing public folders:

• Whether to use one-way or two-way public folder synchronization
• How many public folder synchronization jobs to configure
• What accounts and administrative mailboxes to use for public folder synchronization
• How to configure public folder synchronization collections
• Whether hierarchy reorganization is required
• How public folder deletions are handled
• When public folder resynchronization is required

For more details, see the related topics.

However, note that public folder synchronization is optional and you may skip this procedure if desired.