SnmpKit.SnmpMgr.Walk (snmpkit v2.0.1)

SNMP walk operations using iterative GETNEXT requests.

This module provides efficient walking of SNMP trees and tables using the GETNEXT operation repeatedly until the end of the subtree.

Return shape

Like every other SnmpMgr operation since 1.0, walks return enriched varbind maps, one per object:

%{
  oid: "1.3.6.1.2.1.1.1.0",          # dotted string
  oid_list: [1, 3, 6, 1, 2, 1, 1, 1, 0],
  type: :octet_string,
  value: "System description",
  name: "sysDescr.0",                # when include_names: true (default)
  formatted: "System description"    # when include_formatted: true (default)
}

:name and :formatted can be switched off per call with include_names: false / include_formatted: false, or globally through SnmpKit.SnmpMgr.Config. The pre-1.0 {oid, type, value} tuples are no longer returned by any path; pattern-match on the map keys instead.

Summary

Types

oid()
target()
varbind()

Functions

walk(target, root_oid, opts \\ [])

Performs a walk starting from the given root OID.

walk_column(target, column_oid, opts \\ [])

Walks a specific table column.

walk_table(target, table_oid, opts \\ [])

Walks an SNMP table starting from the table OID.

Types

oid()

@type oid() :: binary() | [non_neg_integer()]

target()

@type target() :: binary() | tuple() | map()

varbind()

@type varbind() :: SnmpKit.SnmpMgr.Format.enriched_varbind()

Functions

walk(target, root_oid, opts \\ [])

@spec walk(target(), oid(), keyword()) :: {:ok, [varbind()]} | {:error, term()}

Performs a walk starting from the given root OID.

Automatically chooses between GETNEXT (SNMPv1) and GETBULK (SNMPv2c) based on the version specified in options.

Parameters

  • target - The target device
  • root_oid - Starting OID for the walk
  • opts - Options including :version, :max_repetitions, :timeout, :community

Examples

{:ok, results} = SnmpKit.SnmpMgr.Walk.walk("192.168.1.1", [1, 3, 6, 1, 2, 1, 1])
# [
#   %{oid: "1.3.6.1.2.1.1.1.0", oid_list: [1, 3, 6, 1, 2, 1, 1, 1, 0], name: "sysDescr.0",
#     type: :octet_string, value: "System description", formatted: "System description"},
#   %{oid: "1.3.6.1.2.1.1.2.0", oid_list: [1, 3, 6, 1, 2, 1, 1, 2, 0], name: "sysObjectID.0",
#     type: :object_identifier, value: [1, 3, 6, 1, 4, 1, 9, 1, 1], formatted: "1.3.6.1.4.1.9.1.1"},
#   %{oid: "1.3.6.1.2.1.1.3.0", oid_list: [1, 3, 6, 1, 2, 1, 1, 3, 0], name: "sysUpTime.0",
#     type: :timeticks, value: 12345, formatted: "2 minutes 3 seconds"}
# ]

# Bare maps without names/formatting:
{:ok, [%{oid: _, type: _, value: _} | _]} =
  SnmpKit.SnmpMgr.Walk.walk("192.168.1.1", "system", include_names: false, include_formatted: false)

walk_column(target, column_oid, opts \\ [])

@spec walk_column(target(), oid(), keyword()) :: {:ok, [varbind()]} | {:error, term()}

Walks a specific table column.

Returns enriched varbind maps (see the module documentation).

Parameters

  • target - The target device
  • column_oid - The full column OID (table + entry + column)
  • opts - Options

walk_table(target, table_oid, opts \\ [])

@spec walk_table(target(), oid(), keyword()) :: {:ok, [varbind()]} | {:error, term()}

Walks an SNMP table starting from the table OID.

Automatically chooses between GETNEXT and GETBULK based on version. GETBULK provides significantly better performance for large tables.

Parameters

  • target - The target device
  • table_oid - The table OID to walk
  • opts - Options including :version, :max_repetitions, :timeout, :community