cluster_database TRUE/FALSE what does it mean in Oracle RAC? I have 3 databases on an Oracle RAC (two nodes) one database which is running with CLUSTER_DATABASE=TRUE on both nodes, the other two runs on each node with CLUSTER_DATABASE=FALSE

what does it mean the CLUSTER_DATABASE value?
and if it is CLUSTER_DATABASE= FALSE, is it as a normal single node Oracle Database?
what happen to the database instance that runs as (CLUSTER_DATABASE=FALSE) when the node is offline? dose it goes online on the other node or it goes offline as well?
What the SIDs on all the nodes? Is this really the same DATABASE. For example you can have 3 node cluster having a single ASM on all the nodes, but database A is clustered on node1/node2. But database B runs only on the node 3.

The database B then is still started and stopped by the Clusterware, but is not clustered. You can also check output from:

ps -ef | grep -e lmd


The lmd process is started on clustered instances only.

EDITED: maybe I understand now. You do not have RAC database. RAC is active-active cluster. .i.e databases instances run on multiple nodes at the same time.

You have standalone instances guarded by Oracle Clusterware. So you have active-passive failover cluster. As described here :Using Oracle Clusterware to Protect
A Single Instance. Then you do NOT need the parameter cluster_database set to true. It only applies to RAC databases.