In this article, I will explain you about Log Shipping technology in SQL Server. After explaining Log Shipping technology, I will show installation and testing of Log Shipping.
Log Shipping technology was released with SQL Server 2000 and it is used now for SQL Server 2012, 2014, 2016, 2017, 2019 Log Shipping technology in SQL Server is also valid for both High Availability and Disaster Recovery. . A backup or secondary database, which is fed periodically from the transaction log of our main database, can serve immediately as a Master database in the event of a disaster. In addition, since our database is protected, it also provides Disaster Recovery solution.
If you want to keep a copy of a production database in case of the disaster, or to use production database again in case of disaster with minimum data loss, we need to use Log Shipping technology. In this technology, the production database is kept as an exact copy on a different server, and this database called secondary database is continuously fed from the production database periodically. Thus, if there is no access to production database or data loss in case of disaster, our secondary database can be used as main database.
we can list the advantages and disadvantages of Log Shipping as follows.
- Provides both Disaster Recovery and High Availability solution.
- It is a very inexpensive technology in terms of cost. From SQL Server 2008, this technology is available in all versions except the express version.
- Easy to install and maintain.
- It is possible to has a lots of logshipping for a database. This is an opportunity to minimize the data loss of an database.
- Secondary database, which is in Standby mode, allows reporting in read-only mode without any manual operation.
- User error can be solved by using old transaction log backups.
- Log Shipping does not have automatic failover , in this case when the failover needs, database administrator must perform manual failover immediately .
- Because of Manual Failover, Downtime is more than synchronous mirroring.
- It is possible to lose data when the main database is corrupt.
I will explain the installation and configuration of Log Shipping in the Next article.