How to make netmon monitor itself

From Netmon

Sometimes it is necessary to monitor important metrics of the Netmon device, such as CPU usage, memory resources, and disk space. This is accomplished by adding Netmon as an SNMP device. We must first setup the SNMP agent on the Netmon server, then add 127.0.0.1 as a device under the Devices screen.

Enabling the SNMP Agent

Install the SNMP Agent:

apt-get install snmpd

Open the configuration file:

pico /etc/snmp/snmpd.conf

Scroll down and find the line that says:

access MyROSystem ""     any       noauth    exact  system    none   none

Change the word system to all:

access MyROSystem ""     any       noauth    exact  all    none   none

Press ctrl+x to exit. Say y to save, and press Enter for the file name.

Restart the SNMP agent:

/etc/init.d/snmpd restart

Adding the Device to Netmon

In the Netmon application, goto Devices. Click Add New Device. For the IP address, enter 127.0.0.1. For name, say me. Click Enable SNMP. Click Add Device button.

Setting Up Alerts for Disk Space

Under Device Explorer, under the me device, click SNMP Walk (full). Under the HOST-RESOURCES mib, find the group of OIDs titled hrStorageDescr. There will be multiple entries for this OID, but find the one with the value /var. Write down the number next to the OID name, eg hrStorageDescr.6, the number is 6. Now find the OIDs named hrStorageSize, using the number you wrote down. Look at the value, it will be a large number like 1218376. If you would like to be alerted when the disk reaches 80%, we must multiply this number by .80. Write down the result: 1218376 * .80 = 974701. Now find the OIDs named hrStorageUsed. Next to the appropriate OID (in our example it is .6), click Add Tracker. Click on Enable Logging and click the Add Tracker button. It will then ask you to configure an alert. For the value, enter the result of our multiplication, in this example it is 974701. Click Add New Alert.

You will now be notified when the Netmon disk reaches over 80%. If you want to specify other percentages, such as %50, then simply multiply hrStorageSize by .50 instead of .80.