Problem with SNMP

[STest6905]

Hello.

I have a gasoline generator that has the ability to report its status via the SNMP protocol. If I use a third-party app, I can get a response from querying "1.3.6.1.2.1.1.1.0" and "1.3.6.1.4.1.28634.6.2551906584.2.8206" and it works well. When I tried to write it myself, I notice that the first request is successful but on the second one I get a "NoSuchName" error.

ps.
Windows 10 x64
RAD Studio XE6
Indy 10.6.0

Here is my simple code:

Code:

procedure TForm2.Button2Click(Sender: TObject);
var
  i: Integer;
begin
  SNMP.Host := '172.17.40.243';
  SNMP.Port := 161;
  SNMP.Community := 'public';
  SNMP.Query.Clear;
  SNMP.Query.Version := 0;

  try
    if not SNMP.Connected then
    begin
      SNMP.Connect;
      Memo1.Lines.Add('Connected');
    end
    else
      Memo1.Lines.Add('Already connected');
  except
    on E: Exception do
    begin
      Memo1.Lines.Add('Error on connect: ' + E.Message);
      Exit;
    end;
  end;

  try
    SNMP.Query.PDUType := PDUGetRequest;
    SNMP.Query.MIBAdd(Edit1.Text, '');
    if SNMP.SendQuery then
    begin
      Memo1.Lines.Add('Value received: ' + SNMP.Reply.Value[0]);
    end
    else
    begin
      Memo1.Lines.Add('Error: ' + IntToStr(SNMP.Reply.ErrorStatus));
    end;

    SNMP.Disconnect;
  except
    on E: Exception do
    begin
      Memo1.Lines.Add('Error: ' + E.Message);
    end;
  end;
end;

This also doesn't work:

Code:

procedure TForm2.Button5Click(Sender: TObject);
var
  SNMP: TIdSNMP;
  dn, PLevel, SRate: string;
  p: Extended;
begin
  SNMP := TIdSNMP.Create(nil);
  try
    SNMP.Host := '172.17.40.243';
    SNMP.Community := 'public';
    SNMP.Query.Version := 6;

    SNMP.ReceiveTimeout := 3000;
    if SNMP.QuickSend('1.3.6.1.2.1.1.1.0', SNMP.Community, SNMP.Host, dn) then
      Memo1.Lines.Add(dn);
    if SNMP.QuickSend('1.3.6.1.4.1.28634.6.2551906584.2.8206',
SNMP.Community, SNMP.Host, SRate) then
      Memo1.Lines.Add(SRate);

    Memo1.Lines.Add('');
  finally
    SNMP.Free;
  end;
end;

In the first case, I have a positive result: (oid=1.3.6.1.2.1.1.1.0)

Code:

Connected
Value received: IB-Lite

In the second case I have an error:

Code:

Connected
Error: 2 (NoSuchName)

If I use a third-party program (MIBViewer), everything works fine:

Code:

Send snmp get request to 172.17.40.243:161
.1.3.6.1.2.1.1.1.0 (not in loaded mib files) --> IB-Lite

Send snmp get request to 172.17.40.243:161
.1.3.6.1.4.1.28634.6.2551906584.2.8213.0 (not in loaded mib files) --> 261

Can anyone tell me what the problem is? I will be very grateful for the information

[rlebeau]

I merged in the information that you had emailed to me privately.

In any case, one discrepancy I see is that MIBViewer is requesting "1.3.6.1.4.1.28634.6.2551906584.2.8213" but you are requesting "1.3.6.1.4.1.28634.6.2551906584.2.8206" instead.  Is that actually the case, or just a typo?

[STest6905]

I merged in the information that you had emailed to me privately.

In any case, one discrepancy I see is that MIBViewer is requesting "1.3.6.1.4.1.28634.6.2551906584.2.8213" but you are requesting "1.3.6.1.4.1.28634.6.2551906584.2.8206" instead.  Is that actually the case, or just a typo?

Thank you for pointing out such a nuance, although the list includes both teams.
8213 - battery voltage.
8206 - the number of hours worked.
In the 111 program, both commands are passed, and in my program, for some reason, none of them are passed, but only the main one.

[STest6905]

And so several dozen subsequent attempts did not yield anything, everything remained as it was. I didn't think of anything smarter than sending a request via UDP... Surprisingly, everything worked without problems...

[rlebeau]

In the 111 program, both commands are passed, and in my program, for some reason, none of them are passed, but only the main one.

Have you tried using a packet sniffer, like Wireshark, to see how the SNMP packets from TIdSNMP differ from the other program's packets? Its certainly possible that TIdSNMP might have a bug that is not creating the packets correctly, but I would need to see the raw packets from a working setup and a non-working setup to verify that.

[STest6905]

Have you tried using a packet sniffer, like Wireshark, to see how the SNMP packets from TIdSNMP differ from the other program's packets? Its certainly possible that TIdSNMP might have a bug that is not creating the packets correctly, but I would need to see the raw packets from a working setup and a non-working setup to verify that.

Yes, I used Wireshark to look at the traffic. Here I can provide you with a sample of this protocol. There is not much data. It was from the successful send that I used the data to send over UDP.