Prerequisites for People Search in SharePoint Server 2010
People search in SharePoint Server 2010 requires the following:
1. Search service application configured.
2. A complete deployment of User Profile synchronization.
3. A Managed Metadata service application.
4. MySite Web application created and configured.
5. Search crawling for MySite configured.
6. A Search Center that uses the Enterprise Search Center template.
Without all of the above prerequisites, you cannot properly configure people search in SharePoint Server 2010.