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What SNMP library for .NET makes traps, sets or gets simple? [closed]

What are the best SNMP libraries to use with .NET? Specifically for listening for traps or sending set or get requests.

Convert snmp octet string to human readable date format

Using the pysnmp framework i get some values doing a snmp walk. Unfortunately for the oid

1.3.6.1.21.69.1.5.8.1.2 (DOCS-CABLE-DEVICE-MIB)

i get a weird result which i cant correctly print here since it contains ascii chars like BEL ACK

When doing a repr i get:

OctetString('\x07\xd8\t\x17\x03\x184\x00')

But the output should look like:

2008-9-23,3:24:52.0

the format is called "DateAndTime". How can i translate the OctetString output to a "human readable" date/time ?

Introduction to SNMP monitoring

I've been tasked with writing a monitoring program for my company's server software that integrates with zenoss via snmp.

To be brief, I can't get anything up off the ground. I think my first goal is to figure out the correct way to write an snmp agent (in any language to start, although it will eventually be in java). Are there any good test harnesses out there? I've used snmptest, which ships with zenoss, but it's not much good to me if I can't get a test agent off the ground. Anything that I know the zenoss manual has a lot of info, but it seems to presume a prior knowledge of standard systems monitoring practices and tools, and I can barely penetrate it.

Also, is it generally a good practice to use snmp to monitor software?

Definition of SNMP Gauge32 vs Counter32

Can someone point me to a good definition of Gauge32 vs Counter32? I understand that Counter32 can wrap, but Gauge32 can't.

I'm trying to understand their semantics. For example, I've heard you should take the difference between two Counter32 readings to get a value/second. Is there something like that for a Gauge32 value?

Thanks for any insight.

SNMP MIB development tool

Does anybody know a good tool to assist in the development of an SNMP MIB with correct formatting and syntax?

If possible, it should be free and run under Linux.

Why is Math.floor() used instead of integer division in BER Codec

I am looking at the SNMPBEECodec which can be seen at this location
In particular I am looking at the function encodeLength()
A snippet I am interested in

        int numBytes = 0;
        int temp = length;
        while (temp > 0)
        {
            ++numBytes;
            temp = (int)Math.floor(temp / 256);
        }   

(from the Drexel SNMP library).

I would like to know why Math.floor() is used instead of just a simple integer division like temp/256. It seems the simple integer division would give the same result. Or is there a technical difference?

SNMP: ASN.1 MIB Definitions. Referencing a table within a table

Its's been a while since I've written ASN.1 so..

Our data model is comprised of several table definitions within a table. This is not workable in SNMP, so we need to flatten the definitions. The easiest way to do this would be to have the embedded table indexed by the same OID as the parent table. Thus

someTableEntry ::= SEQUENCE {
   someTableIndex
        Integer32,
   someTableDomain
        Integer32,
   someTableFooTable
        SEQUENCE OF SomeTableFooTable
} 

becomes

    someTableEntry ::= SEQUENCE {
       someTableIndex
            Integer32,
       someTableDomain
            Integer32,
    } 

someTableFooTable ::= SEQUENCE {
    someTableIndex
       Integer32,
....
} 

The good thing is that in our application there will NEVER be any kind of SET, GET or GET NEXT so no need for SNMP walk (there are some very good reasons for this that supersede the need for network management elegance. All attributes will be reported via traps only. I think this is a valid SNMP MIB definitions but wanted to get some feedback.

Thanks in advance.

How can I write an SNMP agent or SNMP extension agent DLL in C#

I need to write an SNMP agent for my application.

I read the CodeProject article on how to write an SNMP extension agent DLL using win32, but would like to know if it is possible to do it with managed code.

Also, is it possible to write my own SNMP agent in managed code and run it along windows SNMP service? windows SNMP service is required to run on my server to provide the basic operating system management info.

What C# SNMP library would you recommend? I found a few C# SNMP protocol implementations, but could not find sample code on how to implement an SNMP agent - most samples are only about querying other agents or sending traps.

Basic questions about SNMP

I'm learning about SNMP, and writing some applications using it. I have some basic questions about the protocol:

1. Do the agents store its state on the device itself?
2. If there is a trap set on an agent, can you do a poll on the same OID to get the same information?
3. Without using a mib file, is there a way to query a device for all of its information at once? If not, and you're writing your own customized manager, do you have to know the structure of what it reports up front?
4. If you're setting up an agent to report, is there usually a way to control the frequency of how often it sends a trap? Or does it usually send a trap as often as some condition is satisfied?

What is the best open source SNMP monitoring tool? [closed]

I am currently working on software that must emit SNMP traps for SNMP versions 1 & 2 and possibly v3 in the future. I have downloaded several and found them to be either too complex or too simplistic. All I want is to view traps and analyze the data structures within them, and the ability to import my custom MIB's. The best I have found so far is ireasonings MIB Browser, but would be greatful for any nice alternatives.

Running command line silently with VbScript and getting output?

I want to be able to run a program through command line and I want to start it with VbScript. I also want to get the output of the command line and assign it to a variable and I want all this to be done silently without cmd windows popping up. I have managed two things separately but not together. Here's what I got so far. Run the command from cmd and get output:

Dim WshShell, oExec
Set WshShell = WScript.CreateObject("WScript.Shell")
Set oExec = WshShell.Exec("C:\snmpget -c public -v 2c 10.1.1.2 .1.3.6.1.4.1.6798.3.1.1.1.5.1")
x = oExec.StdOut.ReadLine
Wscript.Echo x

The above script works and does what I want except that cmd pops up for a brief moment.

Here's a script that will run silently but won't grab the output

Set WshShell = WScript.CreateObject("WScript.Shell")
Return = WshShell.Run("C:\snmpset -c public -v 2c -t 0 10.1.1.2 .1.3.6.1.4.1.6798.3.1.1.1.7.1 i 1", 0, true)

Is there a way to get these two to work together?

Let me give you a background on why I want do to this. I am basically polling a unit every 5-10 minutes and I am going to get the script to email or throw a message box when a certain condition occurs but I don't want to see cmd line popping up all day long on my computer. Any suggestions? Thanks

Easy to use SNMP client library for c++? [closed]

What's an easy to use SNMP client library for c++?

Why is SNMP usually run over UDP and not TCP/IP?

This morning, there were big problems at work because an SNMP trap didn't "go through" because SNMP is run over UDP. I remember from the networking class in college that UDP isn't guaranteed delivery like TCP/IP. And Wikipedia says that SNMP can be run over TCP/IP, but UDP is more common.

I get that some of the advantages of UDP over TCP/IP are speed, broadcasting, and multicasting. But it seems to me that guaranteed delivery is more important for network monitoring than broadcasting ability. Particularly when there are serious high-security needs. One of my coworkers told me that UDP packets are the first to be dropped when traffic gets heavy. That is yet another reason to prefer TCP/IP over UDP for network monitoring (IMO).

So why does SNMP use UDP? I can't figure it out and can't find a good reason on Google either.

Experimental/private branch for OID numbers in LDAP Schemas?

Attributes or object classes in LDAP schemas are identified through a unique number called OID. Moreover OIDs are also used in the SNMP protocol. Everyone can apply for an enterprise number by the IANA and then define his own subnumbers. But the processing of the application can last up to 30 days.

Does anyone know if there is a "test" branch of OID numbers that could be used for experimental purposes while waiting for an official enterprise number?

How can I parse a raw SNMP trap in Perl?

A few weeks ago I wrote an SNMP relayer for our ops group. They have some dumb devices that can only send traps to a single IP, and we have a monitoring system that listens on multiple IPs for availability. The code's dead simple, and essentially:

while (recv($packet)) {
  foreach $target (@targets) {
    send($target, $packet);
  }
}

It's worked, basically, but now the obvious short coming that it doesn't include the originator IP is an issue (apparently the first class of device included the info as a varbind and some new class does not).

What I would like to do is change my code to something like this:

while ($server->recv($packet)) {
  my $obj = decompile($packet)
  if (!$obj->{varbind}{snmpTrapAddress}) {
    $obj->{varbind}{snmpTrapAddress} = inet_ntoa($server->peeraddr());
  }
  $packet = compile($obj);
  foreach $target (@targets) {
    send($target, $packet);
  }
}

In other words, if my sender isn't including snmpTrapAddress, add it. The problem is that every SNMP package I've looked at for Perl seems very heavily focused on the infrastructure of receiving traps and performing gets.

So: Is there a simple Perl module that will allow me to say "here's a blob of data representing an snmp trap. decode it into something I can easily manipulate, then recompile it back into a blob I can throw over the network"?

If the answer you give is "use SNMP dummy", can you provide examples of this? I may just be blind, but from the output of perldoc SNMP it's not obvious to me how to use it in this manner.

EDIT:

Turns out after looking around a bit that "SNMP encoding" is really ASN.1 BER (Basic Encoding Rules). Based on this I'm having a go with Convert::BER. I would still welcome any easy break down/edit/rebuild tips for SNMP.