We can access and analyze several query and crawl health reports, logs and usage reports from the Search service application in the SharePoint Central Administration to monitor the health of the search system.

The health reports and logs only contain information after a full crawl has completed. To run a full crawl, we have to set up a Search service application, add at least one content source, and then start a full crawl.

To view the health reports and the crawl log, one have to be an administrator of the Search service application. Alternatively, an administrator who is a member of the Farm Administrators group can grant user accounts Read permissions on the Search service application. A user account that has Read permissions can only view the Search service application status page, the health reports and the crawl log.

Query health reports:

1. Trend
2. Overall
3. Main Flow
4. Federation
5. SharePoint Search Provider
6. People Search Provider
7. Index Engine

To view query health reports:

1. Verify that the user account that is performing this procedure is an administrator of or has Read permissions to the Search service application.
2. In Central Administration, under Application Management, click Manage service applications.
3. On the Service Applications page, click the Search service application.
4. On the Search Administration page, in the Quick Launch, in the Diagnostics section, click Query Health Reports.
5. On the Search Service Application: Query Latency Trend page, click the query report that you want to view.

The following table shows which reports are available.

Crawl health reports:

SharePoint 2013 provides the following reports about crawl health:

1. Crawl Rate
2. Crawl Latency
3. Crawl Queue
4. Crawl Freshness
5. Content Processing Activity
6. CPU and Memory Load
7. Continuous Crawl

To view crawl health reports

1. Verify that the user account that is performing this procedure is an administrator of or has Read permissions to the Search service application.
2. In Central Administration, under Application Management, click Manage service applications.
3. On the Service Applications page, click the Search service application.
4. On the Search Administration page, in the Quick Launch, in the Diagnostics section, click Crawl Health Reports.
5. On the Search Service Application: Crawl Reports page, click the crawl health report that you want to view.

The following table shows which reports are available.

Crawl log:

The crawl log tracks information about the status of crawled content. This log lets you determine whether crawled content was successfully added to the index, whether it was excluded because of a crawl rule, or whether indexing failed because of an error. The crawl log also contains information such as the time of the last successful crawl and whether any crawl rules were applied. You can use the crawl log to diagnose problems with the search experience.

To view the crawl log

1. Verify that the user account that is performing this procedure is an administrator of the Search service application, or has Read permissions to it.
2. In Central Administration, under Application Management, click Manage service applications.
3. On the Service Applications page, click the Search service application.
4. On the Search Administration page, in the Quick Launch, in the Diagnostics section, click Crawl Log.
5. On the Crawl Log – Content Source page, click the view that you want.

Additional columns in the Content Source, Host Name and Crawl History views:

Usage reports (search report):

To view usage reports

1. Verify that the user account that is performing this procedure is an administrator of or has Read permissions to the Search service application.
2. In Central Administration, under Application Management, click Manage service applications.
3. On the Service Applications page, click the Search service application.
4. On the Search Administration page, in the Quick Launch, in the Diagnostics section, click Usage Reports.
5. On the View Usage Reports page, click the usage or search reports view that you want view.