vRealize Automation Appliance High Availability
The vRealize Automation appliance supports active-active high availability for all components except the appliance database. Starting with the 7.3 release, database failover is automatic if three nodes are deployed and synchronous replication is configured between two nodes. When vRealize Automation appliance detects database failure, it promotes a suitable database server to be the master. You can monitor and manage the appliance database on the Virtual Appliance Management Console vRA Settings > Database tab.
vRealize Automation appliance provides the environment where services are running in a pre-configured and isolated environment.
If several appliances are joined in a cluster following rules are valid to all of them
On each node there is a equal set of running services
All services share common database
vRA, vRO and Horizon are accessed though external load balancer
On one node the database is running in Master mode, while on the rest nodes databases are configured in Replica mode
When joining a new node to cluster it accepts the same configuration as the rest nodes in the cluster
Services running inside virtual appliance which are managed by automated HA deployment are
vRA core services ( vcac-server ) , this one is the heart of vRA and starting this starts all services
vRO ( vco-server and vco-configurator ) ,
vIDM ( horizon-workspace ) , provides authentication framework int he form of VMware Identity Manager which is embedded in appliance
vPostgres (vpostgres) , embedded Postgres database that contains tables for vRA, vRO and vIDM
Health (vrhb-service), reports functional health of select suite components that's vRA and vRO
Setting these services in HA mode is part of automated process whern new vRA appliance is joined to already running vRA. Once the new appliance is joined to cluster, all services are automatically configured in cluster mode and synchronized against the cluster