If my Governance/Configuration Registry and User Store databases that hook into my WSO2 Identity Server go down, will that bring down my entire cluster since each "IS" node wouldn't be able to share/replicate data between one another since the Registry and User Store are no longer available? How would I load-balance the Registry and User Store so that the unavailability of these databases don't impair the operations of my entire cluster?
Relevant links: https://docs.wso2.com/display/CLUSTER44x/Setting+up+the+Database https://docs.wso2.com/display/CLUSTER44x/Governance+Registry+Deployment+Patterns#GovernanceRegistryDeploymentPatterns-MinimumdistributedHAsetup(withSSO)
High availability on the data persistence layer usually addressed by the Database of you selected. One example is Mysql Master/Slave Replication
This is a JDBC level, client side load balancing, and supported by almost all major JDBC vendors.