telegraf/plugins/inputs/snmp/snmp.go

819 lines
21 KiB
Go

package snmp
import (
"io/ioutil"
"log"
"net"
"strconv"
"strings"
"time"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/plugins/inputs"
"github.com/soniah/gosnmp"
)
// Snmp is a snmp plugin
type Snmp struct {
Host []Host
Get []Data
Bulk []Data
Table []Table
Subtable []Subtable
SnmptranslateFile string
nameToOid map[string]string
initNode Node
subTableMap map[string]Subtable
}
type Host struct {
Address string
Community string
// SNMP version. Default 2
Version int
// SNMP timeout, in seconds. 0 means no timeout
Timeout float64
// SNMP retries
Retries int
// Data to collect (list of Data names)
Collect []string
// easy get oids
GetOids []string
// Table
Table []HostTable
// Oids
getOids []Data
bulkOids []Data
tables []HostTable
// array of processed oids
// to skip oid duplication
processedOids []string
OidInstanceMapping map[string]map[string]string
}
type Table struct {
// name = "iftable"
Name string
// oid = ".1.3.6.1.2.1.31.1.1.1"
Oid string
//if empty get all instances
//mapping_table = ".1.3.6.1.2.1.31.1.1.1.1"
MappingTable string
// if empty get all subtables
// sub_tables could be not "real subtables"
//sub_tables=[".1.3.6.1.2.1.2.2.1.13", "bytes_recv", "bytes_send"]
SubTables []string
}
type HostTable struct {
// name = "iftable"
Name string
// Includes only these instances
// include_instances = ["eth0", "eth1"]
IncludeInstances []string
// Excludes only these instances
// exclude_instances = ["eth20", "eth21"]
ExcludeInstances []string
// From Table struct
oid string
mappingTable string
subTables []string
}
// TODO find better names
type Subtable struct {
//name = "bytes_send"
Name string
//oid = ".1.3.6.1.2.1.31.1.1.1.10"
Oid string
//unit = "octets"
Unit string
}
type Data struct {
Name string
// OID (could be numbers or name)
Oid string
// Unit
Unit string
// SNMP getbulk max repetition
MaxRepetition uint8 `toml:"max_repetition"`
// SNMP Instance (default 0)
// (only used with GET request and if
// OID is a name from snmptranslate file)
Instance string
// OID (only number) (used for computation)
rawOid string
}
type Node struct {
id string
name string
subnodes map[string]Node
}
var sampleConfig = `
## Use 'oids.txt' file to translate oids to names
## To generate 'oids.txt' you need to run:
## snmptranslate -m all -Tz -On | sed -e 's/"//g' > /tmp/oids.txt
## Or if you have an other MIB folder with custom MIBs
## snmptranslate -M /mycustommibfolder -Tz -On -m all | sed -e 's/"//g' > oids.txt
snmptranslate_file = "/tmp/oids.txt"
[[inputs.snmp.host]]
address = "192.168.2.2:161"
# SNMP community
community = "public" # default public
# SNMP version (1, 2 or 3)
# Version 3 not supported yet
version = 2 # default 2
# SNMP response timeout
timeout = 2.0 # default 2.0
# SNMP request retries
retries = 2 # default 2
# Which get/bulk do you want to collect for this host
collect = ["mybulk", "sysservices", "sysdescr"]
# Simple list of OIDs to get, in addition to "collect"
get_oids = []
[[inputs.snmp.host]]
address = "192.168.2.3:161"
community = "public"
version = 2
timeout = 2.0
retries = 2
collect = ["mybulk"]
get_oids = [
"ifNumber",
".1.3.6.1.2.1.1.3.0",
]
[[inputs.snmp.get]]
name = "ifnumber"
oid = "ifNumber"
[[inputs.snmp.get]]
name = "interface_speed"
oid = "ifSpeed"
instance = "0"
[[inputs.snmp.get]]
name = "sysuptime"
oid = ".1.3.6.1.2.1.1.3.0"
unit = "second"
[[inputs.snmp.bulk]]
name = "mybulk"
max_repetition = 127
oid = ".1.3.6.1.2.1.1"
[[inputs.snmp.bulk]]
name = "ifoutoctets"
max_repetition = 127
oid = "ifOutOctets"
[[inputs.snmp.host]]
address = "192.168.2.13:161"
#address = "127.0.0.1:161"
community = "public"
version = 2
timeout = 2.0
retries = 2
#collect = ["mybulk", "sysservices", "sysdescr", "systype"]
collect = ["sysuptime" ]
[[inputs.snmp.host.table]]
name = "iftable3"
include_instances = ["enp5s0", "eth1"]
# SNMP TABLEs
# table without mapping neither subtables
[[inputs.snmp.table]]
name = "iftable1"
oid = ".1.3.6.1.2.1.31.1.1.1"
# table without mapping but with subtables
[[inputs.snmp.table]]
name = "iftable2"
oid = ".1.3.6.1.2.1.31.1.1.1"
sub_tables = [".1.3.6.1.2.1.2.2.1.13"]
# table with mapping but without subtables
[[inputs.snmp.table]]
name = "iftable3"
oid = ".1.3.6.1.2.1.31.1.1.1"
# if empty. get all instances
mapping_table = ".1.3.6.1.2.1.31.1.1.1.1"
# if empty, get all subtables
# table with both mapping and subtables
[[inputs.snmp.table]]
name = "iftable4"
oid = ".1.3.6.1.2.1.31.1.1.1"
# if empty get all instances
mapping_table = ".1.3.6.1.2.1.31.1.1.1.1"
# if empty get all subtables
# sub_tables could be not "real subtables"
sub_tables=[".1.3.6.1.2.1.2.2.1.13", "bytes_recv", "bytes_send"]
`
// SampleConfig returns sample configuration message
func (s *Snmp) SampleConfig() string {
return sampleConfig
}
// Description returns description of Zookeeper plugin
func (s *Snmp) Description() string {
return `Reads oids value from one or many snmp agents`
}
func fillnode(parentNode Node, oid_name string, ids []string) {
// ids = ["1", "3", "6", ...]
id, ids := ids[0], ids[1:]
node, ok := parentNode.subnodes[id]
if ok == false {
node = Node{
id: id,
name: "",
subnodes: make(map[string]Node),
}
if len(ids) == 0 {
node.name = oid_name
}
parentNode.subnodes[id] = node
}
if len(ids) > 0 {
fillnode(node, oid_name, ids)
}
}
func findnodename(node Node, ids []string) (string, string) {
// ids = ["1", "3", "6", ...]
if len(ids) == 1 {
return node.name, ids[0]
}
id, ids := ids[0], ids[1:]
// Get node
subnode, ok := node.subnodes[id]
if ok {
return findnodename(subnode, ids)
}
// We got a node
// Get node name
if node.name != "" && len(ids) == 0 && id == "0" {
// node with instance 0
return node.name, "0"
} else if node.name != "" && len(ids) == 0 && id != "0" {
// node with an instance
return node.name, string(id)
} else if node.name != "" && len(ids) > 0 {
// node with subinstances
return node.name, strings.Join(ids, ".")
}
// return an empty node name
return node.name, ""
}
func (s *Snmp) Gather(acc telegraf.Accumulator) error {
// TODO put this in cache on first run
// Create subtables mapping
if len(s.subTableMap) == 0 {
s.subTableMap = make(map[string]Subtable)
for _, sb := range s.Subtable {
s.subTableMap[sb.Name] = sb
}
}
// TODO put this in cache on first run
// Create oid tree
if s.SnmptranslateFile != "" && len(s.initNode.subnodes) == 0 {
s.nameToOid = make(map[string]string)
s.initNode = Node{
id: "1",
name: "",
subnodes: make(map[string]Node),
}
data, err := ioutil.ReadFile(s.SnmptranslateFile)
if err != nil {
log.Printf("Reading SNMPtranslate file error: %s", err)
return err
} else {
for _, line := range strings.Split(string(data), "\n") {
oids := strings.Fields(string(line))
if len(oids) == 2 && oids[1] != "" {
oid_name := oids[0]
oid := oids[1]
fillnode(s.initNode, oid_name, strings.Split(string(oid), "."))
s.nameToOid[oid_name] = oid
}
}
}
}
// Fetching data
for _, host := range s.Host {
// Set default args
if len(host.Address) == 0 {
host.Address = "127.0.0.1:161"
}
if host.Community == "" {
host.Community = "public"
}
if host.Timeout <= 0 {
host.Timeout = 2.0
}
if host.Retries <= 0 {
host.Retries = 2
}
// Prepare host
// Get Easy GET oids
for _, oidstring := range host.GetOids {
oid := Data{}
if val, ok := s.nameToOid[oidstring]; ok {
// TODO should we add the 0 instance ?
oid.Name = oidstring
oid.Oid = val
oid.rawOid = "." + val + ".0"
} else {
oid.Name = oidstring
oid.Oid = oidstring
if string(oidstring[:1]) != "." {
oid.rawOid = "." + oidstring
} else {
oid.rawOid = oidstring
}
}
host.getOids = append(host.getOids, oid)
}
for _, oid_name := range host.Collect {
// Get GET oids
for _, oid := range s.Get {
if oid.Name == oid_name {
if val, ok := s.nameToOid[oid.Oid]; ok {
// TODO should we add the 0 instance ?
if oid.Instance != "" {
oid.rawOid = "." + val + "." + oid.Instance
} else {
oid.rawOid = "." + val + ".0"
}
} else {
oid.rawOid = oid.Oid
}
host.getOids = append(host.getOids, oid)
}
}
// Get GETBULK oids
for _, oid := range s.Bulk {
if oid.Name == oid_name {
if val, ok := s.nameToOid[oid.Oid]; ok {
oid.rawOid = "." + val
} else {
oid.rawOid = oid.Oid
}
host.bulkOids = append(host.bulkOids, oid)
}
}
}
// Table
for _, hostTable := range host.Table {
for _, snmpTable := range s.Table {
if hostTable.Name == snmpTable.Name {
table := hostTable
table.oid = snmpTable.Oid
table.mappingTable = snmpTable.MappingTable
table.subTables = snmpTable.SubTables
host.tables = append(host.tables, table)
}
}
}
// Launch Mapping
// TODO put this in cache on first run
// TODO save mapping and computed oids
// to do it only the first time
// only if len(s.OidInstanceMapping) == 0
if len(host.OidInstanceMapping) >= 0 {
if err := host.SNMPMap(acc, s.nameToOid, s.subTableMap); err != nil {
log.Printf("SNMP Mapping error for host '%s': %s", host.Address, err)
continue
}
}
// Launch Get requests
if err := host.SNMPGet(acc, s.initNode); err != nil {
log.Printf("SNMP Error for host '%s': %s", host.Address, err)
}
if err := host.SNMPBulk(acc, s.initNode); err != nil {
log.Printf("SNMP Error for host '%s': %s", host.Address, err)
}
}
return nil
}
func (h *Host) SNMPMap(
acc telegraf.Accumulator,
nameToOid map[string]string,
subTableMap map[string]Subtable,
) error {
if h.OidInstanceMapping == nil {
h.OidInstanceMapping = make(map[string]map[string]string)
}
// Get snmp client
snmpClient, err := h.GetSNMPClient()
if err != nil {
return err
}
// Deconnection
defer snmpClient.Conn.Close()
// Prepare OIDs
for _, table := range h.tables {
// We don't have mapping
if table.mappingTable == "" {
if len(table.subTables) == 0 {
// If We don't have mapping table
// neither subtables list
// This is just a bulk request
oid := Data{}
oid.Oid = table.oid
if val, ok := nameToOid[oid.Oid]; ok {
oid.rawOid = "." + val
} else {
oid.rawOid = oid.Oid
}
h.bulkOids = append(h.bulkOids, oid)
} else {
// If We don't have mapping table
// but we have subtables
// This is a bunch of bulk requests
// For each subtable ...
for _, sb := range table.subTables {
// ... we create a new Data (oid) object
oid := Data{}
// Looking for more information about this subtable
ssb, exists := subTableMap[sb]
if exists {
// We found a subtable section in config files
oid.Oid = ssb.Oid
oid.rawOid = ssb.Oid
oid.Unit = ssb.Unit
} else {
// We did NOT find a subtable section in config files
oid.Oid = sb
oid.rawOid = sb
}
// TODO check oid validity
// Add the new oid to getOids list
h.bulkOids = append(h.bulkOids, oid)
}
}
} else {
// We have a mapping table
// We need to query this table
// To get mapping between instance id
// and instance name
oid_asked := table.mappingTable
oid_next := oid_asked
need_more_requests := true
// Set max repetition
maxRepetition := uint8(32)
// Launch requests
for need_more_requests {
// Launch request
result, err3 := snmpClient.GetBulk([]string{oid_next}, 0, maxRepetition)
if err3 != nil {
return err3
}
lastOid := ""
for _, variable := range result.Variables {
lastOid = variable.Name
if strings.HasPrefix(variable.Name, oid_asked) {
switch variable.Type {
// handle instance names
case gosnmp.OctetString:
// Check if instance is in includes instances
getInstances := true
if len(table.IncludeInstances) > 0 {
getInstances = false
for _, instance := range table.IncludeInstances {
if instance == string(variable.Value.([]byte)) {
getInstances = true
}
}
}
// Check if instance is in excludes instances
if len(table.ExcludeInstances) > 0 {
getInstances = true
for _, instance := range table.ExcludeInstances {
if instance == string(variable.Value.([]byte)) {
getInstances = false
}
}
}
// We don't want this instance
if !getInstances {
continue
}
// remove oid table from the complete oid
// in order to get the current instance id
key := strings.Replace(variable.Name, oid_asked, "", 1)
if len(table.subTables) == 0 {
// We have a mapping table
// but no subtables
// This is just a bulk request
// Building mapping table
mapping := map[string]string{strings.Trim(key, "."): string(variable.Value.([]byte))}
_, exists := h.OidInstanceMapping[table.oid]
if exists {
h.OidInstanceMapping[table.oid][strings.Trim(key, ".")] = string(variable.Value.([]byte))
} else {
h.OidInstanceMapping[table.oid] = mapping
}
// Add table oid in bulk oid list
oid := Data{}
oid.Oid = table.oid
if val, ok := nameToOid[oid.Oid]; ok {
oid.rawOid = "." + val
} else {
oid.rawOid = oid.Oid
}
h.bulkOids = append(h.bulkOids, oid)
} else {
// We have a mapping table
// and some subtables
// This is a bunch of get requests
// This is the best case :)
// For each subtable ...
for _, sb := range table.subTables {
// ... we create a new Data (oid) object
oid := Data{}
// Looking for more information about this subtable
ssb, exists := subTableMap[sb]
if exists {
// We found a subtable section in config files
oid.Oid = ssb.Oid + key
oid.rawOid = ssb.Oid + key
oid.Unit = ssb.Unit
oid.Instance = string(variable.Value.([]byte))
} else {
// We did NOT find a subtable section in config files
oid.Oid = sb + key
oid.rawOid = sb + key
oid.Instance = string(variable.Value.([]byte))
}
// TODO check oid validity
// Add the new oid to getOids list
h.getOids = append(h.getOids, oid)
}
}
default:
}
} else {
break
}
}
// Determine if we need more requests
if strings.HasPrefix(lastOid, oid_asked) {
need_more_requests = true
oid_next = lastOid
} else {
need_more_requests = false
}
}
}
}
// Mapping finished
// Create newoids based on mapping
return nil
}
func (h *Host) SNMPGet(acc telegraf.Accumulator, initNode Node) error {
// Get snmp client
snmpClient, err := h.GetSNMPClient()
if err != nil {
return err
}
// Deconnection
defer snmpClient.Conn.Close()
// Prepare OIDs
oidsList := make(map[string]Data)
for _, oid := range h.getOids {
oidsList[oid.rawOid] = oid
}
oidsNameList := make([]string, 0, len(oidsList))
for _, oid := range oidsList {
oidsNameList = append(oidsNameList, oid.rawOid)
}
// gosnmp.MAX_OIDS == 60
// TODO use gosnmp.MAX_OIDS instead of hard coded value
max_oids := 60
// limit 60 (MAX_OIDS) oids by requests
for i := 0; i < len(oidsList); i = i + max_oids {
// Launch request
max_index := i + max_oids
if i+max_oids > len(oidsList) {
max_index = len(oidsList)
}
result, err3 := snmpClient.Get(oidsNameList[i:max_index]) // Get() accepts up to g.MAX_OIDS
if err3 != nil {
return err3
}
// Handle response
_, err = h.HandleResponse(oidsList, result, acc, initNode)
if err != nil {
return err
}
}
return nil
}
func (h *Host) SNMPBulk(acc telegraf.Accumulator, initNode Node) error {
// Get snmp client
snmpClient, err := h.GetSNMPClient()
if err != nil {
return err
}
// Deconnection
defer snmpClient.Conn.Close()
// Prepare OIDs
oidsList := make(map[string]Data)
for _, oid := range h.bulkOids {
oidsList[oid.rawOid] = oid
}
oidsNameList := make([]string, 0, len(oidsList))
for _, oid := range oidsList {
oidsNameList = append(oidsNameList, oid.rawOid)
}
// TODO Trying to make requests with more than one OID
// to reduce the number of requests
for _, oid := range oidsNameList {
oid_asked := oid
need_more_requests := true
// Set max repetition
maxRepetition := oidsList[oid].MaxRepetition
if maxRepetition <= 0 {
maxRepetition = 32
}
// Launch requests
for need_more_requests {
// Launch request
result, err3 := snmpClient.GetBulk([]string{oid}, 0, maxRepetition)
if err3 != nil {
return err3
}
// Handle response
last_oid, err := h.HandleResponse(oidsList, result, acc, initNode)
if err != nil {
return err
}
// Determine if we need more requests
if strings.HasPrefix(last_oid, oid_asked) {
need_more_requests = true
oid = last_oid
} else {
need_more_requests = false
}
}
}
return nil
}
func (h *Host) GetSNMPClient() (*gosnmp.GoSNMP, error) {
// Prepare Version
var version gosnmp.SnmpVersion
if h.Version == 1 {
version = gosnmp.Version1
} else if h.Version == 3 {
version = gosnmp.Version3
} else {
version = gosnmp.Version2c
}
// Prepare host and port
host, port_str, err := net.SplitHostPort(h.Address)
if err != nil {
port_str = string("161")
}
// convert port_str to port in uint16
port_64, err := strconv.ParseUint(port_str, 10, 16)
port := uint16(port_64)
// Get SNMP client
snmpClient := &gosnmp.GoSNMP{
Target: host,
Port: port,
Community: h.Community,
Version: version,
Timeout: time.Duration(h.Timeout) * time.Second,
Retries: h.Retries,
}
// Connection
err2 := snmpClient.Connect()
if err2 != nil {
return nil, err2
}
// Return snmpClient
return snmpClient, nil
}
func (h *Host) HandleResponse(
oids map[string]Data,
result *gosnmp.SnmpPacket,
acc telegraf.Accumulator,
initNode Node,
) (string, error) {
var lastOid string
for _, variable := range result.Variables {
lastOid = variable.Name
nextresult:
// Get only oid wanted
for oid_key, oid := range oids {
// Skip oids already processed
for _, processedOid := range h.processedOids {
if variable.Name == processedOid {
break nextresult
}
}
// If variable.Name is the same as oid_key
// OR
// the result is SNMP table which "." comes right after oid_key.
// ex: oid_key: .1.3.6.1.2.1.2.2.1.16, variable.Name: .1.3.6.1.2.1.2.2.1.16.1
if variable.Name == oid_key || strings.HasPrefix(variable.Name, oid_key+".") {
switch variable.Type {
// handle Metrics
case gosnmp.Boolean, gosnmp.Integer, gosnmp.Counter32, gosnmp.Gauge32,
gosnmp.TimeTicks, gosnmp.Counter64, gosnmp.Uinteger32, gosnmp.OctetString:
// Prepare tags
tags := make(map[string]string)
if oid.Unit != "" {
tags["unit"] = oid.Unit
}
// Get name and instance
var oid_name string
var instance string
// Get oidname and instance from translate file
oid_name, instance = findnodename(initNode,
strings.Split(string(variable.Name[1:]), "."))
// Set instance tag
// From mapping table
mapping, inMappingNoSubTable := h.OidInstanceMapping[oid_key]
if inMappingNoSubTable {
// filter if the instance in not in
// OidInstanceMapping mapping map
if instance_name, exists := mapping[instance]; exists {
tags["instance"] = instance_name
} else {
continue
}
} else if oid.Instance != "" {
// From config files
tags["instance"] = oid.Instance
} else if instance != "" {
// Using last id of the current oid, ie:
// with .1.3.6.1.2.1.31.1.1.1.10.3
// instance is 3
tags["instance"] = instance
}
// Set name
var field_name string
if oid_name != "" {
// Set fieldname as oid name from translate file
field_name = oid_name
} else {
// Set fieldname as oid name from inputs.snmp.get section
// Because the result oid is equal to inputs.snmp.get section
field_name = oid.Name
}
tags["snmp_host"], _, _ = net.SplitHostPort(h.Address)
fields := make(map[string]interface{})
fields[string(field_name)] = variable.Value
h.processedOids = append(h.processedOids, variable.Name)
acc.AddFields(field_name, fields, tags)
case gosnmp.NoSuchObject, gosnmp.NoSuchInstance:
// Oid not found
log.Printf("[snmp input] Oid not found: %s", oid_key)
default:
// delete other data
}
break
}
}
}
return lastOid, nil
}
func init() {
inputs.Add("snmp", func() telegraf.Input {
return &Snmp{}
})
}