SNMP Monitoring and Morningstar Products

What is SNMP?

Simple Network Management Protocol (SNMP) is an internet standard protocol that is used to manage and monitor devices on an IP network. It is typically supported by devices found in IT infrastructures, such as servers, modems, routers, printers, workstations, and other network components.

Using the defined communication standards and management topology, SNMP allows for a simple and convenient way to view the status of critical system components on a private Local Area Network (LAN) or across a WAN (Wide Area Network) if so desired.

Continue to read the frequently asked questions and answers below and view the recording of our System Monitoring with Morningstar Products and SNMP webinar for more information.

What is an NMS?

Network Management Software (NMS) uses SNMP to provision, discover, monitor and maintain computer networks.  Licensed and open-source NMS can use SNMP to monitor information associated with Morningstar products.  Supported platforms can be recommended by Morningstar upon request.  Click here to learn more about Morningstar’s partnership with Zabbix open-source NMS.

Who typically uses SNMP?

IT system operators and network management professionals in the Telecommunications and Internet Service industries.  Others include industrial users with an existing network infrastructure, who may also employ SNMP as an easy way to gather data from network equipment assets on site.  In the Oil & Gas industry where users are engaged in digital oilfield management, SNMP is becoming increasingly popular.

Why does Morningstar support SNMP protocol?

Morningstar devices that have Ethernet capabilities already have strong support for industrial protocols including MODBUS, and also supports HTTP and LiveView, Morningstar’s local web dashboard filling a unique need with an easy to view web page that is readable by any device or operating system’s web browser.  Enabling Morningstar products with SNMP greatly adds to their value proposition.

Telecommunication markets typically already have SNMP infrastructures in place.  It makes sense to add a protocol which allows operators to manage energy data alongside their existing site hardware using tools with which they are already familiar. A very thorough description of all the networking/communication options Morningstar products have to offer is included in the Morningstar Networking and Communications Document.

What Morningstar products support SNMP?

The following products support SNMP natively and don’t require Morningstar’s Ethernet Meterbus Converter (EMC-1) accessory:

  • GenStar MPPT – Provides SNMP Polling: GET & SET commands and Community Strings. SNMP is supported for the GenStar MPPT with firmware version 2.3.0 and later. The latest version of the GenStar firmware is available at www.morningstarcorp.com/firmware/genstar-mppt-firmware/.
  • TriStar MPPT (60A models only) – Provides SNMP traps but not SNMP polling.  If SNMP polling is required the EMC-1 can be used with the TriStar MPPT controller.

The following products support SNMP with the Ethernet Meterbus Converter (EMC-1) accessory:

How do I add SNMP to an existing Morningstar product using the EMC-1?

The EMC-1 enables the transmission of serial data from compatible Morningstar devices to the EMC-1 for remote monitoring, configuration, and control, using an IP-based network connection. This way, many new, powerful integration options for Morningstar products can be activated and used in remote power systems.

SNMP is supported for the EMC-1 with firmware version v15.0 and later. Access the most recent EMC-1 firmware file at https://www.morningstarcorp.com/firmware/ethernet-meterbus-converter-firmware/

View the video to see how to update the firmware: https://www.youtube.com/watch?v=VMN5iO62JQs

What products support SNMP natively without using an EMC-1?

The GenStar MPPT controller supports SNMP natively without using the EMC-1. SNMP is supported for the GenStar MPPT with firmware version 2.3.0 and later. The latest version of the GenStar MPPT firmware is available at www.morningstarcorp.com/firmware/genstar-mppt-firmware/.

TriStar MPPT controllers (60A models only) include built-in ethernet and supports SMTP E-mail and SMS alerts as well as SNMP traps, but does not support SNMP polling. If SNMP polling is required, the EMC-1 can be used with the TriStar MPPT controller.

How do I get the Management Information Base (MIB file) for my product?

The MIB file is the list of available data values (Object Identifiers, or OID’s) associated with each product.  It serves as a directory of what information is available for retrieval from the device with SNMP GET requests. A list of parameters and addresses, along with the industry-standard MIB files for each Morningstar device are contained in a zip file you can download here.

How is data monitored with SNMP?

Data can be monitored using 3rd-party Network Management Software (NMS). NMS uses SNMP to provision, discover, monitor and maintain computer networks. For automatic parsing of the MIB file, as is supported by some NMSs, it is important that the following files be uploaded together in order for the device to be recognized.

  • [DEVICE NAME].mib 
  • MORNINGSTAR.mib
  • EMC-1.mib (when using the EMC-1)

Data can also be retrieved using the following SNMP commands:

  • GET: Method used by the SNMP manager to request information from a SNMP agent on a specific OID.
  • GET NEXT: Method used by SNMP manager to work through an ordered list of OIDs according to the standard MIB hierarchy.
  • GET BULK: A sequence of GetNext requests, allowing a large segment of the MIB hierarchy to be queried by the SNMP manager from a managed device.
  • RESPONSE: Used by the SNMP agent to deliver requested information. Also acts as an acknowledgment.

The GenStar MPPT controller also supports SET commands for certain writable EE settings as defined in the control’s MIB file. SET commands can be enabled or disabled for the GesTar with the Ethernet MODBUS Writes Enable/ Disable setting. The Ethernet MODBUS Writes settings can be adjusted on the meter display only.

How does SNMP compare to MODBUS?

SNMP and MODBUS are both components of the application layer in the OSI model. Where MODBUS is a protocol that can be supported by different physical and data link layers, SNMP is exclusively an IP standard. 

Unlike MODBUS IP, which typically uses the TCP transport layer, SNMP data is usually sent through UDP (User Datagram Protocol), which makes it faster, simpler, and more efficient than the TCP used for our current MODBUS IP-enabled Ethernet stack.

If users are implementing a solar system in either an industrial environment such as a SCADA system or a residential use, MODBUS typically has been the “protocol of choice” for its speed and reliability for both monitoring and control. 

MODBUS is also the protocol platform for the SunSpec data standard widely used in “legacy” inverters and charge controllers, data logging hardware, and even storage systems for interoperability.

In many UPS, backup or telecommunication/network applications, SNMP may be a better choice as it will provide the greatest overall device compatibility and management.

When would I want to use SNMP over other protocols or methods of accessing MS device data?

SNMP would be a good choice for accessing data in systems with an existing IT infrastructure. It is useful for sites that have a centralized network management location or host computer. SNMP is ideal for simple ‘bulk’ status monitoring and data polling of many devices. It can also be useful for implementing system-level alert notifications.

However, if more complex system interaction is needed to alter system operation in real time (i.e using bi-directional control), MODBUS may be preferable in those circumstances. 

What version of SNMP do you support?

SNMP v2c, which offers some useful feature enhancements over v1. Example: ‘GetBulkRequest’ for mass data retrieval of multiple variables in a single request, as opposed to iterative ‘GetNextRequest.’

This version comes without the often unnecessary complexity of application-layer security introduced with v3. The added encryption is often redundant due to existing internal network transport level security of the network.

Are there Security issues to consider with SNMP?

It is recommended to implement SNMP v2c for internal networks or have internal network transport-level security implemented for public or internet-facing devices.

In addition to external network security measures, the GenStar MPPT Controller supports SNMP Community strings. Community strings make it possible to set up Access Control Lists (ACL) or Approved Managers Lists, that limit who can access SNMP data.

What Morningstar products are able to send SNMP Traps?

TriStar MPPT controllers (60A models only) include built-in ethernet and can support up to four (4) SNMP traps, but does not support SNMP polling. 

While the GenStar MPPT and EMC-1 do not support asynchronous SNMP Traps, an SNMP browser running on the Network Management System (NMS)/Manager computer can provide effective alert notification options. Using a polling frequency and conditional logic rules found in the NMS, the browser can be configured to alert the user of abnormalities in system performance.

Can SNMP be used simultaneously with other Ethernet services?

Absolutely– MODBUS TCP, LiveView (HTTP), and SNMP can all be used at the same time as they each represent different services in use in the real-time operating system of the EMC-1. They all use different ports: MODBUS Port 502, LiveView HTTP Port 80, and SNMP Port 161 polling data through an internet gateway.  This flexibility makes them all simultaneously available.

Is it possible for more than one NMS to access TS MPPT simultaneously?

It is possible to use multiple NMS to monitor the same device simultaneously, but a numerical max limit has not been tested or specified by Morningstar and is largely dependent on the network traffic tolerance of the EMC-1, which may be impacted by the volume of OIDs polled, polling intervals, etc. With that said, during our beta-testing, we configured (5) different NMS that all monitored the same set of devices simultaneously via a port-forwarding setup on our LAN. This seemed to operate without any known issues.

 

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