Exchange version conversion is Based on Active Directory Routing

Exchange Server 2007 is based onActive DirectoryThe routing topology of the Directory Service website and the IP website link, which is one of the biggest differences with the previous Exchange Server version. The specific content is as follows.

Are you still waiting to switch from Microsoft Exchange Server 2003 or Exchange 2000 Server to Exchange Server 2007? You will soon enjoy all the commands available in the Exchange command line manager-this command line manager is a great feature that can be quickly mastered by administrators who are used to using the wizard. In addition, you will be very happy to adopt server-based rules and all anti-spam enhancements. However, you may hesitate to discard all routing groups and maintain the mail flow when upgrading the Exchange Organization systematically. No problem. Let me explain it!

New Exchange 2007 route Topology

One of the biggest changes between Exchange Server and Exchange 2007 in earlier versions was to adopt a routing topology Based on Active Directory Service websites and IP site links, instead of using the topology based on the routing group and the routing group connector. Some Exchange administrators may think that they have lost control of the routing topology, but do not worry about it. There are many reasons for doing so. When the Active Directory routing behavior does not match the way you want Exchange mail to flow, you can use the tool provided by Exchange 2007 to adjust it. In addition, the network utilization of Active Directory-based routes increases greatly, and you do not need to maintain the routing topology.

In our Exchange 2007 planning guide, we will focus on all the parts that must be recorded in the current topology. The configuration includes the link configuration of the Active Directory website and IP website, the location of the domain controller and the Global Catalog server, the configuration of the existing routing group and routing group connector, and the location of the currently deployed Exchange Server. I know, this requires a lot of information.

Fortunately, the Microsoft Exchange best practices analysis tool helps you quickly understand your network and whether the current topology applies to Exchange 2007. The tool also recommends improvements that can be made before deploying the first Exchange 2007 server.

By the way, Exchange 2007 and Exchange 2003 behave differently when they coexist with Exchange 2000. Therefore, unless otherwise stated in the document, you may consider that everything that applies to Exchange 2003 also applies to Exchange 2000.

Convert

If you are managing an Exchange server or your Active Directory environment has only one website, you do not have to worry about it. When deploying the first Exchange 2007 Server with the hub transport Server role installed, a routing group connector is established between Exchange Server servers running different versions, this allows you to move your mailbox from an earlier version of Exchange Server to an Exchange 2007 Server to an external domain, and to move any connector to an external domain. If your Exchange organization is running multiple servers, you can modify the default route group connector to add the source and target servers. These configuration changes provide fault tolerance and load balancing.

If your Active Directory forest contains multiple websites, make sure you spend some time planning your conversion. Because two different administrators may manage Exchange Server and Active Directory in your organization, you may not be sure whether the topology created by the Active Directory administrator applies to Exchange Server. However, the reason for defining an Active Directory website is exactly the same as that for defining an Exchange route group. Both of them are designed to optimize communication on the basic network. When you find that the current routing group configuration actually reflects the Active Directory website configuration, it may be a bit unexpected, but it will be very happy. The routing group connector also follows a path similar to the IP website link.

By using the commands in the Exchange command line manager, you can find all information about Active Directory website and IP website link configuration. For example, to view the list of all Active Directory websites in the forest, type the following command:

Get-AdSite | format-list

To view the list of all IP website links configured in the forest and the associated Active Directory website, run the following cmdlet:

Get-AdSiteLink

There are some major differences and similarities between Exchange 2003 and Exchange 2007 in how to execute mail routing. Consider the reason for creating a route group and a route group connector. After these objects are created, they define how the Exchange 2003 Server communicates. Exchange 2003 servers in the same routing group can communicate with each other directly. Exchange 2003 servers in different routing groups must use the routing group connector for communication. Each routing group connector defines the point-to-point connection between routing groups. When there is no point-to-point connection between route groups, SMTP communication must be retransmitted between route groups to reach the target location.

In Exchange 2007, the Active Directory Website member determines which Exchange 2007 servers can communicate directly with another server. Exchange 2007 hub transport server uses an intra-organization send connector (implicitly and invisible !) Relay messages to other hub transport servers, whether they are on the local Active Directory website or remote Active Directory website.

Whenever a mail leaves the range of its route group or Active Directory website, the mail must be routed to its destination. The algorithms used in Exchange 2003 and Exchange 2007 to determine the route path are very similar. These Server versions only consider different configuration objects.
 

Let's use travel as a metaphor

The following uses an analogy to illustrate the Efficiency Comparison Between the Exchange 2007 and Exchange 2003 routing systems.

Imagine that your entire Exchange organization is a country and its transportation system is based on toll roads. Because a toll is charged for each highway, you will definitely choose the lowest-cost route. In Exchange 2003, each routing group represents a city in the country, and the routing group connector is a highway between cities. In Exchange 2003, email routing is like driving to your destination and staying in each city along the way. If you encounter obstacles on the way, such as a bridge being inaccessible, road construction, or long periods of rest for road workers, you must stop and ask for directions and hope to have a proper path to go. Moreover, servers that provide new directions must broadcast bypass routes nationwide. All maps must be updated to reflect the new route. After the obstacle is removed, the map must be updated again. At the same time, the detour will make you farther to your destination.

Exchange 2007 does not work in this way. In Exchange 2007, the Active Directory website represents a city, and the IP website link represents a road, but you fly instead of driving to your destination. Once you know the destination, you will fly over all the cities along the way. If you are unable to land in the destination city due to heavy fog, blizzard, or luggage strike, the plane will only change the direction and land in the appropriate city nearest to the destination. The plane then waits for the destination to improve and continues the flight as conditions permit. The sailing route is parallel to the road, and the toll is still charged for each road. Therefore, you need to select the lowest-cost route before you start your trip, which helps you decide which city the plane will switch to in case of a problem.

If there are no direct flights between the specified two locations, you can specify that some or all flights must land in a transit city before continuing the trip. When multiple people take a plane, just as they send an email to multiple recipients, each person wants to go to a different destination and take the same route first, until the entrance to the respective destination is reached. Then, the plane will stop for a short time, and passengers will switch to the plane as needed to arrive at the destination.

Even better, if you do not agree to charge a toll when traveling on a highway between cities (for example, the fee assigned by the Active Directory administrator to an IP website link ), you can change the fee charged to the Exchange 2007 server. You can change the minimum fare for a flight route and decide whether to transfer the route during the flight.

In Exchange 2007, these transport efficiency benefits your organization:

Adhering to a single and definite route (even if a fault occurs) makes troubleshooting easier. You can easily determine the location where a problem occurs in the routing path and start the investigation at this location. It's not that easy to bypass emails while running them.

Fewer servers are used to process emails. Exchange 2007 uses the basic IP network to eliminate temporary hops between the source server and the target server.

The communication overhead from the server to the server used to update the bypass route in Exchange 2003 is eliminated.

Route when Exchange version coexist

Table 1 compares how Exchange servers of different versions process routes.

Table 1 route differences between Exchange Server versions

When you only have Exchange 2007 servers in your organization, Routing Based on Active Directory websites is a great standalone method. However, as long as Exchange 2003 and Exchange 2007 coexist, the Exchange 2003 Server must still pass the mail to the Exchange 2003 mailbox. This means that you can cancel the routing group and routing group connectors only after all mailboxes have been moved to Exchange 2007. If Exchange 2003 and Exchange 2007 are deployed in the same organization, you must maintain the routing group and the routing group connector during the conversion phase. Taking our transport simulation as an example, Exchange 2007 uses a routing group connector to deliver messages to the Exchange 2003 highway system, and Exchange 2003 uses a reverse connector to deliver messages to the Exchange 2007 airline system. Therefore, the trip may include road driving and air flights, depending on the city of origin and destination.
 

Exchange 2003 and Exchange 2007 "view" are different from each other. Exchange 2003 does not know any information about the websites and website links that constitute the Exchange 2007 routing system. Exchange 2003 regards all Exchange 2007 servers as a large routing group. Compared with Exchange 2003, the adjacent Exchange 2007 servers are geographically close to the Exchange 2007 server located at the other end of the world.

On the other hand, Exchange 2007 understands the two routing systems and the routing group and routing group connector used by Exchange 2003. You may have to create a connector for another route group between an Exchange 2007 route group and any Exchange 2003 route group to ensure that you do not indulge in a scenic route ", it uses the most favorable route.

Table 2 compares mail routes in Exchange 2007 coexistence solutions. Let's take a look.

Table 2 Comparison of Exchange 2003 and Exchange 2007 route Behavior

This article allows you to quickly learn how to switch from a route group to an Active Directory website. In Exchange 2007 Help documentation, you can read a lot of details about how to plan to use the Active Directory website to route messages and coexist with Exchange 2003.

I hope this article will introduce the knowledge of Exchange version Conversion Based on Active Directory routing to help readers.