Ignition/Mysql same PC with redundancy

Our current customer is looking to upgrade their SCADA or switch to Ignition, however they are reluctant to change PC/Server topologies (although depending on this, it may be required).

Current they run 2 PC’s redundantly. The SCADA software they use now simply stores historical data in flat files on the PC. When the master goes down, the secondary takes over. When the master comes back up it resumes control but also back-fills its historical data with what the secondary had logged while it was down.

I apologise because I have not had time to play with this and try things. It appears Ignition would not do this natively.

I’ve ‘heard’/seen examples of mysql being setup mirrored/redundantly in a master-master setup that would seem to accomplish this, however I’m afraid it may be a maintenance nightmare.

Obviously the goal is to have the system not require constant maintenance for this. Does anyone have any experience here ?? Is this even possible to do without being a maintenance nightmare. ?

Again I do believe they ‘might’ be willing to change the topology and have the database be on another machine, which could fall to their IT department to backup etc. As it stands now they like NOT having IT having anything to do with their SCADA.

Thanks in advance :prayer: ,
Mike Donaldson


You could do something very similar from an architecture point of view by simply having 1 mysql database on the master machine. You would need to make sure to configure the connection in Ignition in such a way that it would work from the backup too (the configuration is sync’d between the machines). Then, configure your “history mode” on the backup as “partial”.

When the master goes down, the backup will take over. However, in partial mode, all of the data will just be cached. When the master comes back up, the backup will see that it has been running longer, and will forward all of the data to the database.

Hope this helps, let me know if something isn’t clear.