You need to change the polling method from ICMP to SNMP on 200 nodes you...

 The easiest and fastest way to change the polling method for multiple nodes is to use the Manage Nodes feature in the web console. You can select up to 1000 nodes at a time and edittheir properties in bulk. You can choose the polling method from the available options, such as ICMP, SNMP, WMI, or Agent, and provide the required credentials or settings. This will apply the changes to all the selected nodes without affecting their existing data or alerts. References: Choose the polling method to use in the SolarWinds Platform; Polling Intervals - Best Practices; SOLARWINDS NETWORK PERFORMANCE MONITOR