Abstract-The production database are transactions intensive transactions can be insert, update on the tables, failover is the replica of the production server, if there is any change we have to implement on the production and it will be automatically implemented on failover or standby database. Now a days the data on the production server is increasing and we need extra storage space on production server to keep data and this is same required on the failover. To generate reports from that data will increase load on the production server and can affect the performance of the server. There are also some threats which can cause loss of data from which we have to protect our database like Hardware failure, loss of machine. Replication is one of the methods for Backup of the running database and its immediate failover during failure. This paper represents some parts for the replication techniques, failover, and transaction states.