Check out my High Availability diagrams, also linked below
- Failover Clustering Instances (FCIs, traditional Windows and SQL Server clustering)
- AlwaysOn Availability Groups (AGs) and
and 
(The AG diagrams are from Microsoft) - Log Shipping and configuration screenshots
- Database Mirroring and configuration screenshots
- Database Replication
- Network Load Balancing (actually a Windows technology, but still related to HA)
