I can't seem to find where I set the community string for an SNMP monitor.


You won't find this under Setup because Setup refers to PRTG's setup itself and other global settings. The SNMP Community is considered a credential and as such will be a setting under 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: 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.


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The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.