SNMP configuration example

From Teltonika Networks Wiki

Summary[edit | edit source]

This chapter is a guide on configuring SNMP package to establish communication between devices.

SNMP[edit | edit source]

SNMP (Simple Network Management Protocol) - is widely used in networking management for networking monitoring. SNMP uses MIB (Management Information Base) to organize management data in the form of variables, which describe the system configuration and status.

Trap[edit | edit source]

Traps are alert messages sent by SNMP agent to SNMP manager.

SNMP agent - Teltonika router. Device which sends Trap messages to the manager.

SNMP manager - device which listens for Trap messages from the agents.

Teltonika routers are able to send SNMP Trap messages to the manager on their own when they experience a problem or a situation described in the rules.

Preconditions[edit | edit source]

RUT9xx[edit | edit source]

To setup SNMP first make sure that SNMP package is installed, more information here RUT955 Packages and RUT950 Packages.

OID codes[edit | edit source]

OID code (Object identifier code) - is an address used to identify devices and their status.

SNMP OID MIB Tree.png

OID code is represented by the numbers in the boxes starting from "root".

Number Label Explanation
1 iso ISO is the group that established the OID standard
3 org An organization will be specified next
6 dod The US Department of Defense (established the early internet)
1 internet Communication will be via Internet/network
4 private This is a device manufactured by a private entity
1 enterprise The device manufacturer is classified as an enterprise
48690 Teltonika Teltonika enterprise number

To communicate with Teltonika router the start of the OID code, in this case, will be 1.3.6.1.4.1.48690.

Every configuration or status variable has distinct OID code.

Field Number Explanation
static 1 Static router information (Router name, Modem Imei, Modem model etc.)
gsm 2 Sim card information (Sim State, Operator, Mobile IP etc.)
hotspot 3 Hotspot information (Hotspot ip, users etc.)
Trap 4 Trap messages (Information sent through trap messages)
rut9x5 5 Input/Output information
gps 6 GPS information (Latitude, accuracy etc.)
ethernet 7 Information about router ports

To access variable values, after enterprise number add field number and then specify variable number. For example: .1.3.6.1.4.1.48690.1.7.0 represents router name (48690.1.7.0: Enterprise (48690) - Teltonika, Field (1) - static, Variable (7.0) - routerName). All OID codes can be generated from MIB file, basic OID codes can be found here RUT955 SNMP#SNMP Variables list.

MIB File[edit | edit source]

MIB File can be used with MIB browsers for easier access to configuration and status information variables of the device. Download the MIB file and upload/load it in MIB browser. In this example iReasoning MIB browser was used only for testing purpose.

Networking device configrationexample snmp mib browser v2.png

Generating OID code from MIB File[edit | edit source]

MIB File contains all OID codes. Line containing numbers needed for OID code can be identified by this marking "::=".

Networking device configurationexample snmp mib file oid codes v1.png

All that is left, is to add the numbers together. Example from given MIB File: 1.3.6.1.4.1.48690.1.1.0.

Important note: Do not forget to add .0 at the end of the generated OID code, except to Trap OID codes. Trap OID codes are only used by SNMP agent (router), using them in MIB browser or command line will not give any results.

SNMP Configuration[edit | edit source]

To configure SNMP, first enable SNMP service, leave or change the port, you can leave everything else as it is.

Press "Download" button to download MIB file.

Networking device configurationexample snmp snmpconfiguration v1.png

Testing SNMP with MIB browser[edit | edit source]

Use MIB browser to test if SNMP works. Make sure to use same port and IP address of the router in MIB browser. To enter port number in MIB browser press "Advanced" button (on the right of IP address field).

Networking device configurationexample mib browser port v2.png


To upload/load MIB file press "File" in menu bar (top left side of the window) and press "Load MIBs", make sure to select the MIB file you downloaded from the WebUI. MIB browser lets you walk through all OID codes, or return a distinct variable value. To walk through all OID codes select "walk" in Operation tab (top left of the window). To iterate through OID codes manually, navigate to the desired folder on the left of the MIB browser window and select specific element (Double click). The value of the variable will be printed in the Result Table.

Networking device configurationexample snmp test example v2.png

Testing SNMP with console command[edit | edit source]

We can use snmpget command to get information from router:

$ snmpget -c public -v 2c IP_address:port OID_code

Example:

$ snmpget -c public -v 2c 192.168.1.1:161 1.3.6.1.4.1.48690.1.7.0

Trap Configuration[edit | edit source]

First enable SNMP Trap, then enter Host/IP, Hots/IP is the SNMP manager, computer to which SNMP agent will send Trap messages. If router is connected to PC via ethernet cable, enter the IP address of the interface the router is connected to. You can use ipconfig command on windows, ifconfig on linux to find IP address of the interface to which router is connected. Next choose port, preferably choose port number higher than 1024 so SNMP manager could establish connection without root/admin rights. If you choose to leave default port 162 make sure to launch SNMP manager with admin/root permissions.

Networking device configurationexample trap configurations v1.png

Trap rules[edit | edit source]

Trap rules describe on what event SNMP agent should send Trap messages. There are certain rules which can be set up using Teltonika WebUI depending on physical configuration of the device.

Rule name Value Explanation
Signal strength trap Minimal mobile signal strength Teltonika device will send trap message when mobile signal strength falls lower than specified
Connection type trap This trap does not have value Teltonika device will send trap message when mobile connection establishes or changes
Digital input trap Inactive/Active/Both Teltonika device will send trap message when Digital input value changes to specified value
Digital isolated input trap Inactive/Active/Both Teltonika device will send trap message when Digital isolated input value changes to specified value
Analog input trap Higher/Lower/Both + Voltage value Teltonika device will send trap message when Analog input value fulfills specified requirement
Digital output trap Inactive/Active/Both Teltonika device will send trap message when Digital output value changes to specified value
Digital relay output trap Inactive/Active/Both Teltonika device will send trap message when Digital relay output value changes to specified value

To create new rule chose action and press "Add" button, specify rule values and save.

Example: choose "Connection type trap" action and press "Add" button.

Networking device configurationexample snmp trap rule v1.png


Enable trap rule and press "Save".

Networking device configurationexample snmp new connection rule v1.png


New rule should appear in the main Trap window.

Networking device configurationexample new snmp rule saved v1.png


Testing Trap with MIB browser[edit | edit source]

To test trap messages with MIB browser, open Trap receiver and configure the setting. Make sure to use the same port saved in WebUI configuration.

Note: Preferably open MIB browser with root/admin permissions.

Networking device configurationexample snmp trap receiver config v2.png


To test "Connection type trap" reboot mobile modem. You can reboot modem through Status -> Network window. MIB browser should receive Trap message.

Networking configurationexample received trap v2.png

Testing Trap with Linux Terminal[edit | edit source]

To test Traps with Linux terminal extra configurations and packages are required. All information how to setup Trap listening service and how to test it can be found here Testing Trap With Linux Operating System.