High Availability (HA) refers to a ability to minimize system down time while continuing normal operation of service in the event of hardware, software, or network failure. This ability is a critical element in the network computing area where services should be provided 24/7. A HA system consists of more than two server systems, each of which provides uninterrupted services even when a failure occurs in the other system component.
The CUBRID HA is a high-availability feature applied to CUBRID. The CUBRID HA feature provides services, keeping the database synchronized for multiple server systems. In addition, if a failure occurs in a system where a service is being performed, this feature minimizes the service down time by allowing another system to perform the service automatically.
The CUBRID HA feature has a shared-nothing architecture and performs the following two steps for the data synchronization from the master to the slave database server.
The CUBRID HA feature performs these two steps so that synchronized data is maintained all the time between the master and slave databases. Therefore, if an unexpected failure occurs in the master database where a service is being provided, the slave database server can provide the service without interruption in place of the master database server. After the failback, the synchronization process is performed automatically to maintain the same data.
The CUBRID HA feature monitors the state of the system and CUBRID in real time and uses the Heartbeat solution of the Linux-HA project to automatically perform failover in case of system failure. Heartbeat is installed and runs in every system where a CUBRID server operates.
Note As with the replication feature, the log of a table with the primary key can be multiplicated.
Caution The CUBRID HA feature is supported only in Linux-based systems.