We encountered a problem recently with a two server farm. One server was configured as index and query server. Both servers were delivering pages to users. If a user executed a search on the server which did not run the search services, the Search page returned an error, and we saw the following in the application log and SharePoint logs:
Event Type: Error
Event Source: Office Server Search
Event Category: Gatherer
Event ID: 10032
Description:
Could not create a database session.
Context: Application '2bee214b-e0b9-413b-8d85-c71002287e99'
Details:
The database connection string is not available. (0xc0041228)
Application 2bee214b-e0b9-413b-8d85-c71002287e99: The parent farm application root doesn't exist or access denied. - File:d:\office\source\search\search\searchdll\resourcemanagerimpl.cpp Line:703
Application 2bee214b-e0b9-413b-8d85-c71002287e99: Database session creation error for resource type 0. - File:d:\office\source\search\search\searchdll\resourcemanagerimpl.cpp Line:555
After a great deal of investigation and assistance from the guys at Microsoft, we identified the fault. On the server which had no search services configured, we added the following registry keys, copied across from the server which was running index and query functions: