Unable to retrieve SNMP data

  • Hello,

    This is my first time working with snmp but I can’t get it to work. Hopefully somebody will be able to give me some pointers.

    I got pfsense 2.2.5 running inside virtualbox, connected with a loopback adapter so all the traffic of my host (windows 7) which is running virtualbox is routed through pfsense.

    This works fine.

    The firewall is set to fully open.

    I got the SNMP service setup with port 161, public string test and bind to LAN.
    I got softflowd setup with bind to LAN, my host IP as the host and port 2055.

    I’m using the Solarwinds free netflow analyzer. When I add a new a new device the IP and public string both get accepted and pfsense shows up in the device list, I can even see data flowing on EM0 and EM1.

    However as soon as I start capturing I get an error telling me netflow is not started on the selected interface. It says this on all interfaces.

    I tried changing the bindings in SNMP and softflowd but no matter what I select I always get the same error.

    My goal is very simple. All I want to do is create a graph of in/outbound traffic over a certain period of time.

  • Although this doesn't answer your question directly - check out bandwidthd (Its an package from within pfsense)

    It might satisfy your needs..

  • LAYER 8 Global Moderator

    "graph of in/outbound traffic over a certain period of time."

    You don't really need flows to graph traffic only..  If your wanting ports and source dest IPs is when you would need flows.  Just looking at the interfaces will give you a graph of inbound/outbound traffic totals..

    If you want a graph of say http in/out and https in/out, ftp in/out then sure you would need flows.

    Try just using 1 interface for your flow be it your wan or lan.  Do you really need data from both of them to know what is flowing in and out of pfsense to the internet..

  • Hi,

    By flows you mean something like softflowd? I'm graphing interface traffic with Cacti now but I'd be great if I could also log source and destinations ip's, per IP data usage etc. My main goal however is to be able to export all this data so I can go back in time and generate graphs etc over a certain period. Some pfsense packages are logging all that but as far as I know none of them has the ability to save data for a certain amount of time and retrieve data based on a time search.

  • LAYER 8 Global Moderator

    I think your confusing snmp and flows… You do not normally pull flows from a device - the flows are sent (exported) to the collector from the device.  snmp normally has nothing to do with that... but if your trying to extract flow data via a MIB..  What mib is that exactly??

    "back in time and generate graphs"

    Yeah the RRD graphs already do that for any interface..  If what your wanting to see is traffic flow for a specific IP at a specific time and what protocols..  Yes this is a netflow...  You could export them with softflowd sure, but you wouldn't normally send flows to cacti... I was not aware that cacti was a collector or analyzer? Something like this is where you would send the flows https://www.manageengine.com/products/netflow/

    Or why don't you just install ntop package..  You can view history in ntop..

    Thinking maybe your trying to reinvent a wheel where are are already many shapes and sizes of that wheel ;)

  • From the  OpenNMS server, you can use the snmp-request tool in the $OPENNMS_HOME/bin directory.

    For example, support that the IP address of the target node is, the community string is public, and the SNMP agent is enabled using the default port with SNMPv2, the command should look like this:

    /opt/opennms/bin/snmp-request -c public -v 2c -Ow .

    This is equivalent to execute an snmpwalk like this:

    snmpwalk -One -v 2c -c public system

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