SCP-NPM Sample Questions Answers

An OID (Object Identifier) is a unique identifier for a specific variable in a MIB (Management Information Base) that can be polled or monitored by SNMP (Simple Network Management Protocol). However, not all OIDs are supported by all devices or SNMP agents, which are software components that collect and report the MIB data. If you select an OID that is not supported by the device or the SNMP agent, you will get an “OID not supported” error when you try to create a custom poller for that device in NPM (Network Performance Monitor). This means that the device or the SNMP agent does not have the information for that OID or does not respond to the SNMP request for that OID12.

To resolve this issue, you can try the following steps34:

• Verify that the device supports the OID that you want to monitor. You can use the MIB Browser or the MIB Walk tool to browse the MIB tree of the device and find the OID. You can also check the device vendor’s documentation or website for the supported OIDs and MIBs.
• Verify that the SNMP agent on the device is configured properly and has the latest version. You may need to update the SNMP agent or enable some features or extensions to support the OID. You can also check the SNMP agent’s logs or status for any errors or warnings.
• Verify that the SNMP credentials and settings are correct and match the device’s configuration. You may need to use a different SNMP version, community string, port, or timeout value to communicate with the device. You can also test the SNMP connectivityusing the SNMP Test tool or the Test button in the UnDP (Universal Device Poller) application.
• Verify that there are no network issues or firewalls that are blocking the SNMP traffic between the NPM server and the device. You may need to allow the SNMP protocol and port on the firewall or router, or use a different network path or interface to reach the device. You can also use the Ping or Traceroute tools to check the network connectivity and latency.

References: 1: What is an OID?5, 2: The OID is not supported, 3: Troubleshoot Unknown Nodes, 4: Troubleshoot SNMP issues

 The best way to monitor an SNMP metric that NPM is not monitoring out-of-the-box is to create a custom poller using the Universal Device Poller (UnDP) tool. A custom poller allows you to monitor specific aspects of your network devices using SNMP, by selecting the OIDs that correspond to the metrics you want to collect. You can then assign the custom poller to the devices you want to monitor, and view the results in the Orion Web Console, as charts, tables, or gauges. You can also use custom pollers to create alerts and reports based on the collected data. References: Monitor custom statistics based on OIDs with Universal Device Pollers in NPM, Create a custom poller, Assign Universal Device Pollers to devices monitored in NPM

You can make bulk changes to nodes in NPM using the Manage Nodes feature. This allows you to select multiple nodes and edit their properties, such as the polling method, the polling frequency, the SNMP credentials, the custom properties, and more. You can also use the Edit Nodes feature to assign or unassign pollers to nodes, such as the Universal Device Poller (UnDP), the Hardware Health Poller, the Wireless Poller, and more12. References: 1: Change the polling method for a node3, 2: Manage pollers using Device Studio4

NPM polls static properties, such as interface speed and duplex mode, from the firewall devices using SNMP. NPM also collects traffic statistics, such as bytes in and bytes out, from the firewall interfaces using SNMP or NetFlow. NPM then calculates bandwidth consumption based on the total amount of bytes coming through the firewall over a given time interval. Bandwidth consumption is expressed as a percentage of the interface speed. For example, if a firewall interface has a speed of 100 Mbps and NPM polls 10 MB of bytes in and 10 MB of bytes out in one minute, the bandwidth consumption is 20% [(10 MB + 10 MB) / 100 Mbps * 100%]1. References: Monitor firewalls with NPM, Calculate bandwidth utilization on an interface

Orion Maps show you how entities are connected based on the data collected by the Orion Platform products. To display the connections between the nodes in Orion Maps, you need to enable Layer 2 and Layer 3 topology polling on those nodes. This will allow the Orion Platform to discover the network topology using protocols such as CDP, LLDP, or ARP. You can enable topology polling on individual nodes or in bulk using the Manage Nodes feature in the web console. You can also customize the topology polling settings and frequency on the Orion Polling Settings page. References: Intelligent Maps for SolarWinds Platform products; Understand connections on Intelligent Maps in the SolarWinds Platform; Network Mapping Tool – Automated Network Mapping | SolarWinds

SNMP (Simple Network Management Protocol) is a protocol that allows network managers to monitor and control network devices using a set of standardized messages and data structures. SNMP uses a client-server model, where the network manager (client) sends requests to the network device (server) and receives responses. The network device has an SNMP agent that collects and reports the data using a MIB (Management Information Base), which is a hierarchical database of variables that describe the device’s status and configuration. Each variable in the MIB has a unique identifier called an OID (Object Identifier), which is a dot-separated sequence of numbers that follows a tree structure12.

To retrieve a single value in SNMP, you can use two types of requests: GET and GET NEXT. A GET request asks for the value of a specific OID, and the SNMP agent responds with the value if it exists, or an error if it does not. A GET NEXT request asks for the value of the next OID in the MIB tree, and the SNMP agent responds with the value and the OID of the next variable, or an error if there is no next variable. A GET NEXT request can be useful for discovering the OIDs and values of a device, or for iterating over a table of values34.

A GET VALUE request is not a valid SNMP request, and a GET TABLE request is not a single request, but a series of GET NEXT requests that retrieve all the values in a table . References: 1: SNMP Basics, 2: SNMP Tutorial Part 1 – Understanding MIBs and OIDs, 3: SNMP Tutorial Part 2 – SNMP Get, GetNext, GetBulk, 4: SNMP Commands, : SNMP Table Operations, : SNMP Table Retrieval

High Traffic Utilization alerts are triggered when the interface’s received or transmitted percent utilization exceeds a specified threshold. However, this may not reflect the actual network congestion, as traffic spikes can occur momentarily and then subside. To avoid false alerts, you can configure the alert to trigger only when the traffic utilization remains high for a sustained period, such as 5 minutes or more. This way, you can filter out the transient traffic peaks and focus on the persistent issues that affect the network performance. References:

• How do I create a high transmit percent utilization alert to monitor interface bandwidth
• Trouble with High receive percent utilization alert
• How alerts work

An alert limitation is a filter that restricts the scope of an alert to a specific set of objects, such as nodes, interfaces, applications, or groups. You can use an alert limitation to create an alert that only applies to a select set of nodes in your network, and exclude the rest. To set an alert limitation for the nodes to be included in the alert, follow these steps1:

• Click Alerts & Activity > Alerts > Manage Alerts.
• Find the alert that you want to edit or create a new alert.
• On the Trigger Condition tab, define the condition that triggers the alert, such as Percent Loss is greater than or equal to 50.
• On the Scope of Alert tab, select Limit the scope of this alert to a specific subset of objects.
• Choose the method to define the subset of objects, such as Select objects manually, Use a custom SWQL query, or Use a custom SQL query.
• Select or enter the criteria to filter the objects, such as the node name, IP address, group, custom property, or any other attribute.
• Click Add Selected Objects to add the objects to the alert limitation.
• Click Next and complete the rest of the alert configuration.

You can now save and enable the alert, and it will only notify you when packet loss meets or exceeds 50% for the nodes that you have selected in the alert limitation. References: 1: Limit the objects an alert applies to

 Capacity Forecast Charts in NPM show the usage trends and forecasts for nodes, interfaces, and volumes based on historical data. By default, 7 days of data are required to generate these charts1. You can change this setting globally or individually for each object2. Capacity Forecast Charts are available for the following metrics: CPU utilization, memory usage, space usage, receive utilization, and transmit utilization3. References: 1: Monitor capacity usage trends on the network and forecast capacity issues in NPM - Capacity forecasting is available for nodes, interfaces, and volumes that meet the following requirements 2: Change capacity forecasting settings globally in NPM - Change the number of days of historical data required for capacity forecasting 3: Monitor capacity usage trends on the network and forecast capacity issues in NPM - Capacity forecasting is available for the following metrics of monitored nodes, interfaces, and volumes monitored

PerfStack is a feature of the Orion Platform that allows you to compare and correlate performance data from multiple SolarWinds products and entities in a single view1. You can drag and drop metrics from different sources, such as NPM, SAM, NCM, NTA, and more, and create custom dashboards that help you troubleshoot complex network issues2. PerfStack can also show historical data and baselines for comparison3. References: 1: Network Performance Monitor Administrator Guide - Use PerfStack to troubleshoot issues 2: Network Performance Monitor Getting Started Guide - Troubleshoot your network with PerfStack 3: SolarWinds Certified Professional Program - Diagnostics and Troubleshooting Exam Study Guide - Use PerfStack to troubleshoot issues

You can import device-specific MIBs into the SolarWinds MIB Database, and you can also import UnDP pollers based on OIDs from device-specific MIBs. UnDP stands for Universal Device Poller, which is a tool that allows you to monitor custom statistics based on OIDs with NPM. You can create UnDP pollers by selecting OIDs from the MIB Browser, or by importing them from a file that contains OIDs and poller names. You can then assign UnDP pollers to devices monitored by NPM and view the results on the web console. References:

• Monitor custom statistics based on OIDs with Universal Device Pollers in NPM - SolarWinds
• Import Universal Device Pollers - SolarWinds
• SCP Study Aid - SolarWinds (page 7)

 NetPath is a feature of NPM that helps you identify network problems faster by automatically creating a map of the problem area, with a wide variety of supporting information. NetPath displays the performance details of devices inside and outside of your network. NetPath can analyze paths to any network segment, whether it is on-premise, cloud, or hybrid. NetPath uses distributed monitoring and path analysis to discover how applications are delivered through the network to your users. You can deploy agents on Windows computers that act as synthetic users and use advanced probing to discover and test the network path that traffic takes to any network endpoint, such as your local file print server, your website, or external websites. NetPath can also incorporate data from NPM, NCM, and NTA about your on-premises gear, as well as data from the Internet nodes and providers12. References: 1: Discover your network paths in NPM3, 2: NetPath - Easy Visual Network Path Analysis | SolarWinds4

Universal Device Pollers (UnDPs) are custom pollers that allow you to monitor specific aspects of your network devices using SNMP. You can apply UnDPs to any object type that supports SNMP polling, such as interfaces, nodes, and volumes. You cannot apply UnDPs to applications, because they are not SNMP-based objects. Applications are monitored using Application Performance Monitor (APM), which uses different methods, such as WMI, scripts, or agents, to collect data. References: Monitor custom statistics based on OIDs with Universal Device Pollers in NPM, Assign Universal Device Pollers to devices monitored in NPM, Add and assign Universal Device Pollers

Capacity planning is available for the following metrics of monitored nodes, interfaces, and volumes: CPU utilization on nodes, memory usage on nodes, space usage on volumes, receive(in) utilization on interfaces, and transmit (out) utilization on interfaces1. Capacity planning allows you to monitor capacity usage trends on the network and forecast capacity issues based on historical data and customizable thresholds. You can view capacity forecasting graphs and tables on the details views of nodes, interfaces, and volumes, or use the Top XX Capacity Problems widget to see a list of objects whose usage trend is rising2. References: Monitor capacity usage trends on the network and forecast capacity issues in NPM, Forecast capacity for nodes, interfaces, or volumes in NPM

By default, NPM uses the global critical CPU threshold for node statuses, which is 90%. However, you can override this threshold for individual nodes by editing their properties and specifying a custom value for the critical CPU threshold. This way, you can adjust the threshold according to the specific characteristics and performance of each node. Changing the critical CPU threshold on the node will affect how the node status is calculated and displayed in the web console, as well as how the alerts are triggered based on the CPU utilization. References: Thresholds in the SolarWinds Platform; CPU Critical Threshold - Forum - Network Performance Monitor (NPM) - THWACK

 Device Studio is a feature in the SolarWinds Platform Web Console that allows you to create custom pollers for devices or technologies that are not supported by default in NPM. You can use Device Studio to create pollers for CPU and memory, as well as other metrics, by defining the object identifiers (OIDs) and formulas that you want to poll. Device Studio currently supports SNMP and WMI polling technologies, and you can test, assign, and edit your custom pollers from the Manage Pollers page. References: Create pollers in Device Studio for NPM, Device Studio, Device Studio Poller.

To show the connection between two devices on an Orion map, you need to meet the following requirements1:

• The devices must be monitored by NPM.
• The devices must support topology and be interconnected.
• The devices must have the corresponding interfaces monitored and identified as full or half duplex.
• The Orion Maps feature must be enabled and configured.

If you do not see the connection between two devices on an Orion map, you should first verify that you are monitoring Layer 2 and 3 topologies for the devices. You can do this by checking the NPM Network Topology widget on the device details page. This widget will reflect what connections will be automatically drawn in Orion Maps2. If the widget does not show the expected connection, you may need to enable topology polling for the devices or check the SNMP credentials and configuration3.

If you are monitoring the correct topologies and still do not see the connection, you can build a custom connection between the devices using the Orion Maps feature. In the Map Editor, you can add the two devices to the canvas, select them, and click the Connect Objects button. Here you can specify the interface on either side and choose to add the manual connection to the database2.

Building a new Orion map and adding the related entities instead of the nodes will not resolve the issue, as the related entities are based on the same topology data as the nodes. Changing the monitoring method from SNMP to CLI will not resolve the issue, as CLI is not supported for topology polling3.

References: Orion Maps; Orion Map Devices not connect - Forum; Polling methods used by Orion.

One possible reason for not being able to show the polled results as charts on the Orion Web Console is that you did not set the poller to collect historical statistics. Historical statistics are required for displaying charts and gauges in the web console, as they provide the data points for plotting the trends and values over time. If you only set the poller to collect current statistics, you will only be able to view the polled results as tables or lists in the web console. To set the poller to collect historical statistics, you need to edit the poller and select the Keep Historical Data option in the Poller Properties page. You can also specify the retention settings for the historical data, such as the frequency and duration of data collection and storage1. References: Create a custom poller

One possible reason why you have not received any emails for the high CPU load alert is that the alerts are muted on the devices. Muting alerts means that the alert conditions are still evaluated, but the alert actions are not executed. This can be useful when you want to temporarily suppress notifications for planned maintenance or testing. You can mute alerts for individual nodes, groups, or applications, or for all alerts in the Orion Platform. To check if the alerts are muted on the devices, you can go to the Manage Nodes page and look for the Muted column. You can also use the Mute Alerts widget on the Orion homepage to see the status of alert muting. To unmute alerts, you can either use the same widget or the Unmute Alerts option in the node, group, or application details page. References: Mute alerts, Manage nodes, Mute Alerts widget