Essential SharePoint 2007, 2nd Edition

Appendix A. Upgrading

There are three different approaches to upgrading an existing WSS 2.0 or SharePoint Portal Server 2003 installation to WSS 3.0 or MOSS 2007, which can be summarized as follows:

For this type of installation	Use this recommended approach
Small deployment with few customizations	In-place upgrade
Large deployment with customizations	Side-by-side (gradual) upgrade
Farm deployment with hardware upgrade	Database migration

Table A-1 lists the differences between each approach.

Table A-1. Approaches to upgrading

Approach	Description	Advantages	Disadvantages
In-place	Sites are replaced with new version.	Simple Site URLs don't change	Can't be undone Sites are offline during upgrade
Side-by-side	Both versions of SharePoint run on the server and site collections are moved one at a time.	Can revert if needed Reduces time sites are offline	Site URLs may be different during upgrade
Database migration	Content databases are copied and then upgraded in place.	Can revert if needed Minimizes time offline Allows deployment to new hardware	Complex Site URLs may be different during upgrade

Before You Upgrade

Before you upgrade, complete these tasks:

• Review your hardware to verify that there is enough disk space for the type of upgrade you are planning.

• Review your existing SharePoint installation to verify that it is up-to-date.

• Run the pre-upgrade scan tool (PRESCAN.EXE) to find custom site definitions and customized (unghosted) pages.

• Perform a trial upgrade of one or more site collections.