Awesome

AgentX

A library with a pure Go implementation of the AgentX-Protocol. The library is not yet feature-complete, but should be far enough to used in a production environment.

The AgentX-Protocol can be used to extend a snmp-daemon such that it dispatches the requests to an OID-subtree to your Go application. Those requests are than handled by this library and can be replied with metrics about your applications state.

State

The library implements all variable types (Integer, OctetString, Null, ObjectIdentifier, IPAddress, Counter32, Gauge32, TimeTicks, Opaque, Counter64, NoSuchObject, NoSuchInstance, EndOfMIBView), but only some of the requests (Get, GetNext, GetBulk). Set-requests and Traps are not implemented yet.

Helper

In order to provided metrics, your have to implement the agentx.Handler interface. For convenience, you can use the agentx.ListHandler implementation, which takes a list of OIDs and values and serves them if requested. An example is listed below.

Example

package main

import (
    "log"
    "net"
    "time"

    "github.com/posteo/go-agentx"
    "github.com/posteo/go-agentx/pdu"
    "github.com/posteo/go-agentx/value"
)

func main() {
    client, err := agentx.Dial("tcp", "localhost:705")
    if err != nil {
        log.Fatalf(err)
    }
    client.Timeout = 1 * time.Minute
    client.ReconnectInterval = 1 * time.Second

    session, err := client.Session()
    if err != nil {
        log.Fatalf(err)
    }

    listHandler := &agentx.ListHandler{}

    item := listHandler.Add("1.3.6.1.4.1.45995.3.1")
    item.Type = pdu.VariableTypeInteger
    item.Value = int32(-123)

    item = listHandler.Add("1.3.6.1.4.1.45995.3.2")
    item.Type = pdu.VariableTypeOctetString
    item.Value = "echo test"

    item = listHandler.Add("1.3.6.1.4.1.45995.3.3")
    item.Type = pdu.VariableTypeNull
    item.Value = nil

    item = listHandler.Add("1.3.6.1.4.1.45995.3.4")
    item.Type = pdu.VariableTypeObjectIdentifier
    item.Value = "1.3.6.1.4.1.45995.1.5"

    item = listHandler.Add("1.3.6.1.4.1.45995.3.5")
    item.Type = pdu.VariableTypeIPAddress
    item.Value = net.IP{10, 10, 10, 10}

    item = listHandler.Add("1.3.6.1.4.1.45995.3.6")
    item.Type = pdu.VariableTypeCounter32
    item.Value = uint32(123)

    item = listHandler.Add("1.3.6.1.4.1.45995.3.7")
    item.Type = pdu.VariableTypeGauge32
    item.Value = uint32(123)

    item = listHandler.Add("1.3.6.1.4.1.45995.3.8")
    item.Type = pdu.VariableTypeTimeTicks
    item.Value = 123 * time.Second

    item = listHandler.Add("1.3.6.1.4.1.45995.3.9")
    item.Type = pdu.VariableTypeOpaque
    item.Value = []byte{1, 2, 3}

    item = listHandler.Add("1.3.6.1.4.1.45995.3.10")
    item.Type = pdu.VariableTypeCounter64
    item.Value = uint64(12345678901234567890)

    session.Handler = listHandler

    if err := session.Register(127, value.MustParseOID("1.3.6.1.4.1.45995.3")); err != nil {
        log.Fatalf(err)
    }

    for {
        time.Sleep(100 * time.Millisecond)
    }
}

Connection lost

If the connection to the snmp-daemon is lost, the client tries to reconnect. Therefor the property ReconnectInterval has be set. It specifies a duration that is waited before a re-connect is tried. If the client has open session or registrations, the client try to re-establish both on a successful re-connect.

Project

The implementation was provided by simia.tech (haftungsbeschränkt).

License

The project is licensed under LGPL 3.0 (see LICENSE file).