what is the recommended architecture for Sharepoint Search? Is it important to have a separate server? we have crawler on same server and it is taking a lot of hours to complete a Full crawl, causing a performance issue. Is it standard practice to use a separate server just for crawling?
It depends on how much data it's indexing. If it's taking a few hours to complete, I'd recommend moving it to another server. Also, consider running the full indexer less frequently, and schedule it during a low point so it doesn't affect performance as much (i.e. 2am Saturday morning).