Need to configure the alert displayed in alert dashboard , if collector fails to communicate with the LM server.

Hello Thangadurai,

First, we highly recommend that you configure a "Collector Down" escalation chain to associate with the "Collector Down Notification" on the Collector itself.  This will alert you(via email, sms, or phone call) to loss of collector connectivity to the LM cloud. 

https://www.logicmonitor.com/support/settings/collectors/what-if-my-collector-goes-down/

If you want to see this in a dashboard, then I would suggest creating an "Alert List" widget, filtering on just the collector device and by severity of critical which will show you any critical level issue with the collector device.

Regards,

-Troy