Monitoring CPU, Memory, Disk Using SNMP

OpManager helps you monitor the performance metrics of any device that supports SNMP. The monitors for CPU, Memory, and Disk Utilization are automatically associated for the SNMP devices based on the device template definitions.

For example, consider you've associated SNMP-based monitors to the default template for a server type (say Linux) in OpManager. So from then on, all Linux servers discovered into OpManager will have those SNMP-based resource monitors associated by default. This doesn't apply only for just one device category, but these definitions can be used to associate related monitors to any SNMP-enabled device.

If you do not see these monitors associated to the devices, it could be due to any or all of the following reasons:

  • These monitors are not present in the device template.
  • SNMP is not enabled on the device. In such case, enable SNMP and add the monitors to the device once again.
  • Incorrect SNMP credentials are associated. Check the credential details like the SNMP version, community string etc.

Steps to add the monitors to the device again:

  1. Navigate to Inventory -> Devices and then click on a device to open its snapshot page.
  2. From the Snapshot page of the device, select the Monitors tab.
  3. From the monitor types, select Performance Monitors.
  4. You can see the monitors currently associated, along with the active monitors. Click the Actions button on the top-right corner.
  5. From the list of monitors, select the SNMP monitors for CPU, Memory, and Disk Utilization.
  6. You can also add other monitors like Partition monitors etc. if required.
  7. Once done, click 'Add'. The selected monitors are associated to the device and the related metrics will be monitored.

To check if the SNMP agent in the device returns response, try the following:

  • Click the Test Monitor icon against any of the associated monitor names. It does a dynamic query to the device for the value of the selected resource, and show the data.
  • Incase the agent does not respond, you see a message to this effect.

It is recommended to use WMI or CLI to monitor Windows or Linux devices respectively. But if both these protocols aren't available or if you want to monitor additional metrics using SNMP, you can also do that in OpManager.