Alpiron Fail-Safe Controller

Redundancy for Alpiron Suite

What it does

Redundancy in the Alpiron Suite system is achieved through the establishment of a Failsafe Controller to back up the primary Alpiron Controller.  In the event of an Alpiron Suite Controller failure the Alpiron Failsafe Controller will take over the functionality of the primary controller and will notify the IT Administrator by email and SMS.

How it works

To establish an Alpiron Failsafe environment, two Alpiron server instances must be installed on two separate server devices. The first instance will be configured as Primary while the other will be configured as Secondary instance; at the same time the Secondary instances will be told which is the Primary instance.  During normal operations, the Secondary instance will monitor the Primary, making sure it is well and running.  In case of failure, the Secondary instance will take over as to be a Primary and start controlling and executing policies.

Data Sharing

Alpiron Suite utilizes MS SQL database as the repository for all data including policies; when running a Failsafe environment, this data must be shared between the installed Primary and Secondary instances of Alpiron Controller.
 Two different options for sharing data between Alpiron Controller instances are available to the IT Administrator:

Data Sharing - Partial Redundancy

The Primary and Secondary uses the same SQL Server, optionally running on a third server device.

• Pros: Easy to configure and install.
• Cons: A single point of failure still exists unless the system has other external mechanisms in place such as SQL clustering with automatic fail over.

Data Sharing - Full Redundancy

In this configuration, each of the Primary and Secondary Alpiron Controller instances has its own Database instance installed on its associated server.  The two separate databases should be in sync; this may be achieved by using inherent SQL Server features like replication and mirroring.

• Pros: full redundancy and fail safety.
• Cons: Requires minimum SQL Server Standard Edition (as opposed to Alpiron Suite default SQL Express).  Configuration is more complex.

Further Specs

In all other respects, the Alpiron Failsafe Controller resembles the Alpiron Controller.