In a multiple server SharePoint farm, you often find yourself modifying the Search Service Application topology at some point in the initial configuration process. The scenario is that you typically go into your Search Service Application, add query components or indexers, and then save your topology changes. Sometimes, when the process doesn’t work, you might find yourself looking at a timeout error when you go to commit your changes. There are probably a number of reasons that this can occur. I can going to provide you with a few things that you can check should this error occur for you.
First, go to Services on Server in Central Administration. Check each server involved with the topology change and verify that the SharePoint Server Search service shows that it is Started. If it is stuck on Starting, there is a potential issue. At this point, go to the Windows Services control panel and see if the SharePoint Server Search 14 service is started there. Likely it isn’t. If the service isn’t started, you can attempt to fix this in a number of ways. You can try to start the service manually from the Windows Services control panel. You can stop the service with PowerShell and attempt to restart it (more involved). Lastly, you can just try rebooting the server in question. Rebooting usually will work.
Once SharePoint shows the service as started in Services on Server, you can go try to make your topology changes again in the Search Service Application. If all goes well, the changes should complete after several minutes.