Exchange Server 2010: Migration considerations and best practices

Transcription

1 E-Guide Exchange Server 2010: Migration considerations and best practices Many issues can arise when upgrading from Exchange Server 2007 to Exchange 2010 since the two must coexist while data is being migrated. During this coexistence time period is where many organizations experience unexpected issues. This expert e-guide from SearchExchange.com explains top issues to watch for during your Exchange Server 2010 migration, including edge transport issues and issues managing distribution groups. And learn why client access server coexistence may not be that terrible, though the disappearance of single instance storage should be cause for concern. Sponsored By:

2 E-Guide Exchange Server 2010: Migration considerations and best practices Table of Contents Issues to watch for during an Exchange Server 2010 migration Potential coexistence troubles during Exchange 2010 migrations Resources from Dell, Inc. and Intel Sponsored By: Page 2 of 8

3 Issues to watch for during an Exchange Server 2010 migration SearchExchange.com When upgrading from Exchange Server 2007 to Exchange 2010, Microsoft requires that you perform a clean Exchange 2010 installation onto a separate server and then migrate mailbox and public folder content to the new server. You can no longer perform an in-place upgrade. Because of this, Exchange 2007 and Exchange 2010 must coexist from a short period of time while data is being migrated, to as long as "indefinitely." No matter how long the coexistence lasts, many Exchange organizations experience unexpected issues during that time. Here are a few problems you may encounter and their fixes. Edge transport server issues There appears to be some confusion as to how the edge transport server works in an Exchange 2007/Exchange Server 2010 coexistence situation. When you deploy an Exchange 2007 edge transport server, you must create an edge subscription on your hub transport server. The edge subscription links the edge transport server to Exchange Server 2007's transport pipeline. Like Exchange 2007, Exchange Server 2010 also includes both a hub transport server role and an edge transport server role. During coexistence, an Exchange 2007 hub transport server resides alongside an Exchange 2010 hub transport server without any problems. And you can continue to use an Exchange 2007 edge transport server indefinitely. However, things get tricky when you begin to phase out your Exchange 2007 servers. Exchange 2007 doesn't allow you to uninstall the hub transport server role without first deleting the edge subscriptions that are bound to that server. When you delete these subscriptions, it has an effect similar to orphaning your edge transport server. Sponsored By: Page 3 of 8

4 If you're trying to phase out your Exchange 2007 servers, the method is to deploy an Exchange 2010 edge transport server. Not only can this server peacefully exist with your edge transport servers, but you can load balance SMTP traffic across multiple edge transport servers. When you deploy your first Exchange 2010 edge transport server, it must be subscribed to an Exchange 2010 hub transport server. You can't subscribe an Exchange 2010 edge server to an Exchange 2007 hub transport server. Once you have two parallel edge servers and two parallel hub transport servers in place, you can change the MX record to point to your Exchange 2010 edge transport server. After verifying that mail flow is working, you can remove the edge subscription from the Exchange 2007 hub transport server and decommission both the Exchange 2007 hub transport and edge transport servers. Issues when managing distribution groups A common complaint after migrating to Exchange 2010 is that the new server breaks distribution group management. When a user opens Outlook 2007 and attempts to manage his or her distribution groups, he receives the following error message: Changes to the distribution list membership cannot be saved. You do not have sufficient permissions to perform this operation on this object. By default, Microsoft designed Exchange Server 2010 so that users cannot manage their own distribution groups unless they have specific permissions to do so. To give users the ability to manage their distribution groups, go into the Exchange Control Panel and follow these steps: 1. Choose the option to manage My Organization. 3. Select the User Roles option, which is found in the Users and Groups section. 5. Select the Default Role Assignment Policy and click the Details button. Sponsored By: Page 4 of 8

5 7. Check the My Distribution Groups box (Figure 1). Figure 1. By selecting the My Distribution Groups check box, you can allow users to manage their own groups in Exchange If you don't want to give users the ability to create and remove distribution groups, Microsoft created a script that removes the option completely. Sponsored By: Page 5 of 8

6 Potential coexistence troubles during Exchange 2010 migrations By Brien Posey, Contributor, SearchExchange.com If you re migrating from Exchange Server 2007 to Exchange 2010, several coexistence issues are bound to happen. In this tip, Exchange expert Brien Posey explains why client access server coexistence may not be that terrible, though the disappearance of single instance storage should be cause for concern. A big Exchange 2007 to Exchange Server 2010 migration complaint has to do with Microsoft s guidelines for client access server (CAS) coexistence. An Exchange team blog post on dealing with CAS coexistence discusses issues like why you need to assign new URLs to the Exchange 2007 CAS and why you need to acquire new SSL certificates. Most issues the Microsoft team addresses involve Exchange organizations that use multiple Active Directory sites. Environments with Internet-facing CAS servers located behind an HTTP proxy such as an ISA Server or ForeFront Threat Management Gateway can also experience problems. Organizations with a single Active Directory site that only use the CAS server to access OWA have it easy since OWA 2010 is incompatible with Exchange 2007 mailboxes. If a user attempts to log into OWA via an Exchange 2010 CAS, he will automatically be redirected to an Exchange 2007 client access server. If you only use OWA internally, you don t have to perform any special configurations; however, users will need to learn a new OWA URL. If OWA is accessible from outside the organization, you may have to point the OWA URL to your Exchange 2010 CAS server. You ll also need to make sure that the new CAS server s SSL certificate matches the URL. Lastly, verify that the Exchange 2007 CAS server certificate is still valid after redirecting the external URL. Sponsored By: Page 6 of 8

7 Effects of removing single instance storage in Exchange 2010 As Exchange server mailboxes increase in size and number, I/O requirements grow exponentially. Since Exchange Server 2010 was designed to be scalable enough to host millions of mailboxes, it was important to drive down I/O requirements. Unfortunately, database performance improvements come at a price. By simplifying the database, Microsoft eliminated single instance storage (SIS). Previously, if a user sent a 1 MB message to 100 people, it would only consume 1 MB of within the database because only one copy of the message would have been stored. However, if the user sent the same message to 100 Exchange Server 2010 recipients, the message would consume 100 MB of space because Exchange stores 100 copies of the message. Typically, 100 MB isn t a lot by today s standards, but a single message consuming 100 MB is a big deal. Companies migrating from Exchange 2007 will find that mailboxes grow after they ve have been moved; and mailbox databases grow much more quickly than they did in Exchange This design change may have other consequences beyond bloated databases. You may find that you need to increase mailbox quota sizes to accommodate the new database format. You might also need to rethink your backup strategies. Sponsored By: Page 7 of 8

8 Resources from Dell, Inc. and Intel Presentation Transcript: Exchange 2010 Roadmap Series - Transition and Migration Exchange 2010 Roadmap Series: Virtualization Presentation Transcript: Exchange 2010 Roadmap Series - Backup and Recovery About Dell, Inc. and Intel Dell and Intel are strategic partners in delivering innovative hardware solutions to solve your most challenging IT problems. Together we are delivering virtualization optimized solutions to maximize the benefits of any virtualization project. Sponsored By: Page 8 of 8