Search Server Upgrade Options

Microsoft Search Server 2008 is due to be released later this year. It is a subset of SharePoint Server 2007, containing Windows SharePoint Services (the free add-on to Windows Server 2003 or later) and Search Center (indexing and search). You can currently download a release candidate of Search Server Express Edition

The release candidate includes two new features that will be included with Search Server 2008 and also available as an add-on for SharePoint Server 2007 later this year: 1. A new unified administration console to make it easier to configure and manage your index, and 2. Federated search - the ability to return results from multiple indexes. See previous blog posts for more info: Microsoft Enterprise Search Announcements

The following table shows UNsupported upgrade paths:

From	Cannot Upgrade To
SharePoint Server 2007 SharePoint Server 2007 for Search	Search Server 2008 or Search Server 2008 Express
Search Server 2008 or Search Server 2008 Express Edition BETA or RC*	Search Server 2008 or Search Server 2008 Express RTM*
Search Server 2008 or Search Server 2008 Express with SQL Express	SharePoint Server 2007, Search Server 2008 or Search Server 2008 Express with SQL Server (full product versions

Points worth highlighting:

1. There is no supported upgrade from the current release candidate. By all means evaluate it but don't get married to the release candidate. The only way to keep any sites you create would be use backup/restore tools (such as STSADM) to move the sites from the release candidate to a fresh installation of the RTM product
2. There is no supported upgrade from using SQL Express to a full version of SQL Server (Standard, Enterprise, Developer...) This could be a problem if you plan to start small (the Express Editions are all free add-ons to Windows Server with no additional licensing requirement but can only be installed on a single server - no load balancing or clustering possible) and later want the database to scale up and out
3. You can upgrade Windows SharePoint Services v3.0 to Search Server 2008 but the database edition will need to match - i.e. if WSS is running MSDE, it will only upgrade to SQL Server Express; if WSS is running full SQL Server, it must remain full SQL Server
4. You can upgrade Search Server 2008 or Search Server 2008 Express Edition to SharePoint Server 2007 but the database must be full SQL Server.

To understand the differences between Search Server 2008 and SharePoint Server 2007, see previous blog post - Enterprise Search Product Comparison

The information in this blog post is based on the release candidate and it is possible the supported/unsupported upgrade options may change between now and when the product is formally launched. This is not an official Microsoft statement. Check their web site for more information: www.microsoft.com/enterprisesearch

* RC = Release Candidate (pre-RTM preview: product is still in development, does not include any support and features may change), RTM = Release To Manufacture (product is finished, launched and includes support for bug fixes)