Redundant SQLTags drivers (ie: external to Ignition driven by a different product)
Redundant 7.3.1 gateways
Redundant history databases
So while testing this setup I’m trying a number of failure modes, first up is failed SQLTag databases.
Switch off main SQLTags database (and driving app) and everything keeps working just fine. Cool!
Make a change to a tags meta data through Ignition.
Switch off main SQLTag database (and driving app) and change is still there in Ignition. Cooler!
Check backup db for change. Not there Not so cool.
Make another change to Tag meta data. Now the new change and the last one are in the backup. Ok.
Restore main SQLTag DB.
Ignition still has the new change. main DB has the old change
So, a backup database has to be externally synced with the main db and somehow the main db has to be externally synced with the backup after its been restored.
Is there any way that the gateway can be made to write to both databases?
edit: After a system restart, the gateway has the correct (read last) information.
When does the gateway load the SQLTag data from an external tags db?