Where do I set the community string for an SNMP sensor?
The SNMP Community is considered a credential and as such will be a setting on the "Device Tree" (Head to "Devices" to see the Device Tree).
If you're going to use one community string for the whole deployment, you can simply configure this community on the "Root" object, who's address is https://prtg/group.htm?id=0&tabid=8
Within the settings tab of root, scroll down until you locate Credentials for SNMP Devices, configure it as required/desired.
On a deployment where you need multiple different credentials (i.e. community strings) you can configure the SNMP Credentials at Probe, Group or Device level, they all have the Credentials for SNMP Devices in their settings tab. Please keep in mind that like other settings in PRTG, the SNMP Credentials will be inherited by all objects below the level where you configure it, unless overwritten at a lower level: PRTG Manual: Object Hierarchy. Further information can be found here
