Log Shipping overview

Database Log Shipping is been around since SQL Server 7.0, It's a High Availability solution at the Database Level. It is categorized as a "Warm Standby" which means that the Secondary Database Server or the Fail-Over Partner is not always in-sync with the Primary Database Server and the main reason for it is because the Primary Server does not send the transaction as it happens to the second database server. Log Shipping is controlled by the SQL Server Agent Job, what happen is the primary server has a backup job that back-ups the transaction log at a specified intervals to a network share, then the secondary server will copy the transaction log and apply it in the Secondary Server.