PRTG Manual: Layer 2 Trace
The Layer 2 Trace tool uses the network discovery results to calculate the path between two devices. The path is calculated using the connectivity results for the currently loaded discovery result.
The Layer 2 Trace tool can be launched from the 'Tools' tab available on the main page of UVexplorer. Layer 2 Trace is also available from the device context menu in either the device grid or the topology map. When launched from the map the layer 2 trace tool is populated with the selected device. When launched from the map if two devices are selected both devices are populated in the tool. If more than three devices are selected the tool will not be populated with any devices.
In order to perform the trace both a source and target device must be selected. Which device is chosen as the source will not affect the results other than to reverse the direction of the trace. If there is no calculated path between the devices the results will display a message indicating such. Once both devices are selected the results of the trace will be displayed in the results grid. The trace results contains each device participating in the trace path beginning with the source device and ending with the target. If any network devices are involved in the path they will be displayed in-order. A network device will usually participate in the path twice once on the interface connecting to the source path and once on the interface connecting to the target path; in some cases these interfaces will be the same and will appear only once. Since the path represents an ordering sorting of the results is unsupported.
Once the devices are selected and the trace is displayed, the status of the current path can be found by pressing the 'Ping' button. The ping operation will attempt to both ping the device and query the interface status of the device (where available). The interface status query will only be performed if the device has an interface involved in the link and valid SNMP credentials are associated with the device. See Managing Device Credentials for more information about associating credentials.
The 'Device' column contains the display name of the device participating in the trace path.
The 'IP Address' column contains the primary IP address of the device participating in the trace path.
The 'Interface' column contains the display name of the device interface participating in the trace path.
The 'Ping Status' column displays the UP or DOWN status of the ping attempt. This column will only be populated if the ping operation has been performed.
The 'IF Status' column displays the interface UP or DOWN status for the interface participating in the trace path.
