The Simple Network Management Protocol is a standard way of managing devices connected to networks based on the Internet Protocol. Each SNMP "manager" can monitor in detail the operation of remote devices -- "clients" -- such as switches and routers and, in some cases, reconfigure them as well. In particular, the SNMP standard includes a mechanism for having clients send asynchronous notifications -- "traps" -- to managers at the time events deemed significant happen. You can configure your Ubuntu computer to receive and process SNMP traps from clients.
Press the "Ctrl", "Alt" and "F1" keys at the Ubuntu login prompt to bring up a text-mode login prompt. Log in as your regular user. Ubuntu will present you with a command-line prompt, a "shell".
Elevate the shell's privileges to superuser by typing the following command:
Press "Enter." Type your password, and press "Enter" again.
Download and install the SNMP manager utilities by typing the following command:
apt-get install snmpd
Open file "/etc/snmp/snmpd.conf" with a text editor, search for the line containing the words "master agentx" and remove the initial "#" character from that line. Save the file and exit the editor.
Open file "/etc/snmp/snmptrapd.conf" with a text editor and add the following line at the end of the file:
Save the file and exit the editor.
Type the following commands to start the SNMP manager services and the logging of incoming traps:
/etc/init.d/snmpd restart snmptrapd -P -F "%02.2h:%02.2j TRAP%w.%q from %A\n"
Press "Enter" after each line. At that point, snmptrapd will be listening for incoming SNMP traps. When snmptrapd receives a trap, it will log it to standard output, indicating the time of the day, the trap code and the host name of the device that originated the trap.