If the SQL Cluster Insight monitor is indicating DOWN even after giving credentials, check the following cases:
Please check if you have given credentials in both the active and passive nodes. If the credentials have been updated only in the passive node, then the insight monitor will indicate Down.
If the credentials are updated in only one node that was once active, the Insight monitor will indicate Down when that node becomes passive. If you only give the credentials to all the nodes in the SQL cluster setup, the failover can be detected and reflected in the insight monitor.
Irrespective of the number of nodes in your cluster, only one SQL Insight Monitor will be added for monitoring. When the failover occurs, the active node will start sending the insight metric data.
Refer to the SQL insight monitor troubleshooting article for more information.
If you still face issues, please zip the entire <agent installation dir>\monitoring folder from the active node of your SQL cluster and send it to support@site24x7.com.