Index search and multitenancy
Only a single search index can be created for all tenants. The content that is indexed is determined by the user who runs the index update task. Only content that is visible to that user is indexed. Therefore, this task should be performed only by a member of the System Administrators role from the Cognos namespace.
Because there is only one index for all tenants, members of a tenant should not create or run index update tasks. Doing this would affect the index for all tenants.
When a user performs a search, the search results display only entries that are either public or from the user's own tenant. All other results are filtered out by the search service. This ensures that members of one tenant never see content that belongs to other tenants.
For more information, see Managing Index Search.