Revision 1.1.0, released on Mar 30, 2024#

  • Upgraded pysnmp-lextudio to 6.1.

Revision 1.0.6, released on Mar 05, 2024#

  • Locked pysnmp-lextudio to 5.0 to avoid breaking changes in 6.0.

Revision 1.0.5, released on Oct 15, 2023#

  • Fixed IPv6 endpoint support (by kbaikov).

Revision 1.0.4, released on Sep 16, 2023#

  • Merged patches from inexio.

Revision 1.0.3, released on Sep 16, 2023#

  • Merged other pull requests on upstream.

Revision 1.0.2, released on Sep 16, 2023#

  • Fixed a few bugs in snmpsim-record-mibs.

Revision 1.0.1, released on Jan 26, 2023#

  • Added data and variation folders back to package.

Revision 1.0.0, released on Nov 13, 2022#

  • Command-line tools refactored into entry-points and renamed for better clarity and name spacing for the upcoming tools:

    • -> snmpsim-command-responder

    • -> snmpsim-record-commands

    • -> snmpsim-record-mibs

    • -> snmpsim-record-traffic

    • -> snmpsim-manage-records

  • Python 2.4-2.6 support has been dropped.

  • Converted integration tests from depending on to local, autonomous test suite.

  • Replace getopt with argparse in all CLI tools The latter is way more advanced and Pythonic.

    Due to differences in getopt vs argparse usage model, slight changes in tools’ behavior is not impossible.

    Some legacy, backward compatibility CLI options have been dropped by way of this change.

  • Remove execfile use on Py2.

  • Split monolithic command responder onto many specialized modules and two command responder applications: one implementing fully-fledged SNMPv3 architecture (supporting all SNMP versions) and the other implementing just v1 and v2c. The second one is lighter on the resources.

    So we now have two daemons:

    • snmpsim-command-responder

    • snmpsim-command-responder-lite

  • Add activity reporting feature

    On every query, SNMP simulator command responder calls its “reporting” subsystem. If configured, it invokes one of the “modules” responsible for doing something with request information.

    Included modules (“fulljson” and “minimaljson” reporters) accumulate and periodically dump JSON documents containing request counters scoped by SNMP command processing steps.

    Future modules may just send out the information to external collectors e.g. Graphite/Carbon or store it in some other format e.g. Prometheus.

Revision 0.4.9, released on XX-11-2022#

  • Changed web site to

Revision 0.4.8, released on XX-08-2019#

  • Code base PEP8’ed

  • Added support for SNMP Context Engine ID mapping to the file system paths. This feature allows for every single SNMP engine to simulate multiple SNMP contexts based on different .snmprec files. On top of that, this feature simplifies the mapping of empty SNMP community and context names to .snmprec files.

  • Added support for simulation based on compressed .snmprec files using bzip2 compression algorithm (.snmprec.bz2), as well as recording straight into this compressed format. By way of implementing this change, all snmpsim tools have been generalized to variate and record using any of the supported simulation file formats (for as long as chosen format supports variation or recording).

  • Run snmpsimd variation modules initialization under non-privileged user

  • MIB resolution failure handling improved in mib2dev

  • Rearranged documentation, removed public SNMP simulator page

  • Fixed crash caused by pysnmp failing to load up the rest of its MIBs when snmpsimd is switched into non-privileged user

  • Fixed wrong cache directory and files ownership when switching snmpsimd from privileged into non-privileged user

  • Fixed .snmpwalk hex string parser

  • Fixed hex value evaluation error on Python 3 when produced in bytes by a variation modules

  • Fixed ‘\’ evaluation in escaped strings (tag 4e)

  • Fixed redis variation module to run under Py3

  • Fixed broken indices clean-up, especially on Mac OS

  • Fixed broken multiplex module initialization

  • Fixed broken NULL value parsing in .snmpwalk files

Revision 0.4.7, released on Feb 09, 2019#

  • Added missing SNMP PDU error-status values to the error variation module

  • Fix to define PrivilegesOf on Windows

Revision 0.4.6, released on Jan 25, 2019#

  • The –log-level option added

  • Default daemon syslog service destination to a local socket

  • Fixed timed log file rotation to respect log file creation time when computing next rotation time

  • Fixed possible file permission issues by initializing pysnmp modules, logger and variation modules subsystems under reduced user privileges

  • Improve error reporting in notification variation module

Revision 0.4.5, released on Dec 30, 2018#

  • Copyright notice bumped up to year 2019

  • Bumped upper Python version to 3.7

  • Use absolute paths of Simulator data files and variation modules and reflect that in the log – that should ease troubleshooting

  • Optional .snmprec tag modifier is ignored by the error, delay, writecache and notification variation modules

  • Fixed DBM file index detection code to operate correctly

  • Fixed pysnmp/pyasn1 debugging flags print out in –help to work with newer pyasn1/pysnmp

Revision 0.4.4, released on Feb 20, 2018#

  • Fixed regression to non-snmprec format evaluator when called in a non-simulation context (e.g.

  • Fixed non-functional SQL isolation level setup at the sql variation module

Revision 0.4.3, released on Feb 12, 2018#

  • Copyright notice bumped up to year 2018

  • Fix to strip labels from enumerations when producing .snmprec file

  • Fix to SNMP GET command processing by the non-snmprec storage backends - it used to return next OID instead of noSuchObject

Revision 0.4.2, released on Dec 22, 2017#

  • Python literal string representation added as a new flavor of .snmprec string type field (4e)

  • Migrated references from SourceForge

  • Integer and enumerations parsing of snmpwalk output improved

  • Added strong AES privacy algorithms with Blumenthal key localization

  • Fixed SNMP crypto algorithm identifiers to be named consistently after key length rather than MAC length

Revision 0.4.1, released on Oct 29, 2017#

  • SHA2 authentication protocol suite added.

  • Sphinx documentation added based on the original web-site user manual

  • Simulator’s SNMPv3 command line option processing hardened to make easier to understand.

  • Notification variation module now accepts hex strings in var-binds

  • Fixes to Windows path to log file handling.

  • Fixes to MIB objects command-line parsing.

  • Source code PEP8’ed

Revision 0.3.1, released on Jan 21, 2017#

  • Fix to __doc__ use in to make -O0 installation mode working.

  • Copyright notes added to source code files.

  • Per-OID access control added to ‘writecache’ variation module.

  • Data file binary search performance improved

  • Option –string-pool-file for tool implemented

  • Default string pool for tool changed to a pangram

  • Author’s e-mail changed, copyright extended to year 2017

  • Fix to PID file creation when running Python 3.

  • Fix to tool that apparently stopped working.

  • Fix to snmpwalk Timeticks parser

  • Fix to stopping prematurely iterating over OIDs in MIB

  • Fix to accidentally expanded shebang in console scripts (hopefully)

Revision 0.3.0, released on Sep 28, 2015#

  • Simulator now depends on the latest pysnmp features introduced in pysnmp version 4.3.0

  • Introducing initial MIB compiler (PySMI) integration. Most command-line tools can now be given MIB symbols rather than OIDs. Requested MIBs will be automatically downloaded from .

  • New Redis-backed variation module implemented to let users record into and replay simulation data from noSQL key-value store optionally involving server-side Lua scripting.

  • Full-line comments (#-based) and empty lines are now allowed in data files.

  • When recording .snmprec data, hex everything if a non-alpha/numeric literal is present in a value. This eliminates possible issues with unescaped contents in a SQL-based recorder.

  • New –max-varbinds option can now be used for limiting the number of variable bindings in SNMP response message on a per-engine-id basis. Global default is now 64 variable bindings.

  • Multiple SNMP ContextEngineID can now be configured per each of possibly many SNMP Engine IDs.

  • SNMP configuration logging reworked for better clarity.

  • The notification module now binds to the same local interface through which Simulator received CommandRequest triggering notification. Also it supports ‘bindaddr’ option to override the above behaviour on a per-OID basis.

  • The sql variation module not switches default SQL transaction isolation level to ‘READ COMMITTED’. Isolation level (0-3) could now be specified on per-instance basis through ‘isolationlevel’ option.

  • The subprocess variation module improved to expose more SNMP engine parameters to user process.

  • Switched to the latest pysnmp’s requestObserver facility for getting request details from pysnmp core.

  • Numeric module’s ‘function’ parameter now accepts optional arguments.

  • The tool improved to optionally survive SNMP PDU-level errors and keep walking remote Agent using an OID derived from the failed one.

  • Configurable SNMP request timeout and retry count settings now supported by the tool.

  • The –context-engine-id option support added to tool.

  • Hex values can now be passed to –v3-context-* options to tool

  • Variation modules options separators can now be escaped by doubling or tripling them.

  • All logging moved to Python logging framework. Some more log targets (such as remote syslog) added.

  • Low-level SNMP and ASN.1 debugging implemented for all relevant scripts.

  • Configure both plain-text and hashed versions of snmpCommunityName, contextName whenever its length does not exceed 32 chars. That might ease ContextName usage for Agent addressing.

  • Wheel distribution format now supported.

  • Fix to log file autorotation feature.

  • Fix to not to loose the last trailing OID in capture.

  • Fix to variation module recordContexts isolation to make it dedicated to each Variation Module+Agent instance.

  • Fix to snmpEngine configuration code at variation module.

  • Fixes to –logging-method formatting in –help output.

  • Fix to module value wrapping feature.

  • Fix to MIB selection code to prevent (and report) LCD access.

  • Multiple comma-separated debug options now supported.

  • PostgreSQL is now supported by sql variation module.

  • Fix to variation module to work with Python older than 2.5.

  • Fix to variation module to avoid ‘Unread result found’ MySQL error.

  • The snmpwalk OPAQUE: Float: syntax is now supported.

  • Fix to HEX value handling in snmpwalk format handler.

  • Fix to absolute file log path on Windows.

  • Fix to off-by-one errorIndex as reported by and variation modules.

  • Fix to record parsers/builders to fail on empty values.

  • Fix to & in part of processed OIDs counting.

Revision 0.2.4, released on Oct 04, 2013#

  • A tool for building SNMP Simulator data files from network packet captures added.

  • Automatic online data file index rebuild on data file timestamp change implemented.

  • The sql variation module tweaked to be better compliant with Python DB API 2.0 so that it can now work with MySQL out of the box. Module options also reworked to support named DB connect() parameters.

  • Simulator can now run many independent SNMP engines each with its own set of data files listening at dedicated transport endpoints. At least pysnmp 4.2.5 is required for this feature to work.

  • Simulator now accepts the –transport-id-offset command-line parameter to specify the initial transport ID instance for each transport domain configured.

  • Variation module API changed to allow recording module to communicate to its host time of the next probe to occur.

  • Variation module API changed so that SNMP engine ID is only available in variate() context. This is due to the new multi-engine ID design.

  • New –args-from-file command-line parameter added to to allow a large number of SNMP engines configured to Simulator. The –agent-endpoint*-list= family of options discontinued in favor of multiple –agent-*-endpoint options read from args file.

  • Distribute is gone, switching to setuptools completely.

  • Default logging destination for all tools is now stderr.

  • The –version option of renamed into –protocol-version.

  • New command-line option –pid-file added.

  • Daemonization under a non-root user now works.

  • Fixes to time-based log file rotation implementation.

  • Fixes to numeric variation module. Also, taglist parameter is now defaulted into all numerical types.

  • Fix to PID file creation on daemonization.

  • Fixes to stdio binary mode write to work with Python 3.

Revision 0.2.3, released on Aug 01, 2013#

  • Simulator now supports a list of interfaces to listen on through the –agent-endpoint*-list=<file> family of options. It’s intended for simulation a very large pool of devices.

  • Introducing new command-line utility “” designed to manage data files. Features include: merging, splitting, sorting, de-duplicating, conversion between data file formats.

  • Automatic log file rotation feature implemented.

  • A number of improvement to the tool:

    • Columnar objects for table indices are now automatically populated from index values

    • Tables are can now be populated with arbitrary number of rows

    • Hex values can now be given at the prompt using the 0x syntax

    • Default automatic value ranges for integers are now much smaller to increase a chance of automatic selection.

    • Values ranges can now be set for each SNMP type separately.

    • When generating values, make N probes choosing random values for better automation

    • Produced values are sorted and de-duplicated.

    • Fix to OID range checking when specified at the command-line.

  • Help messages made more readable and complete.

  • Data file search code fixed (not to crash Simulator in corner cases) and simplified.

  • Variable conflict fixed that broke –v2c-arch option operations.

  • Fix to OIDs ordering in –v2c-arch GETBULK responder.

  • Fix subprocess variation module to work with old Python(s).

  • Source code linted and improved.

Revision 0.2.2, released on May 13, 2013#

  • Multiple USM user entries with potentially different auth&priv settings can now be configured to

  • Centralized logging facility added. Logging into syslog or file is now supported.

  • Simulator process daemonization and privileges drop implemented.

  • More logging added into, and variation modules to ease the understanding of their operation.

  • The –quiet flag of now deprecated in favor of “null” logging method.

  • Variation modules execution environment extended to provide contexts for three scopes: record, agent and module. This simplifies modules implementation in terms of storing and managing state/configuration information on per-OID/per-Agent and global basis.

  • The tool now supports DNS names in c/l target parameter.

  • New ‘cumulative’ flag added to the variation module.

  • The multiplex module improved to allow .snmprec file selection via SNMP SET.

  • Fatal exceptions are now fully logged.

  • Type checking is now performed on SET operation at writecache module.

  • Fix to community names ‘/’-normalization at transport address based variation logic. It appeared broken on Windows only since 0.2.1.

  • Fix to behaviour on missing variation module directory.

  • Fix to .snmpwalk grammar parser to support Network Address type tag.

  • Fix to module to let its multiple instances working independently (each for a subtree).

  • Multiple fixes and re-work of the module

  • Fix to tool to write snmprec data to stderr in binary mode.

  • Fix to OID search in a .snmprec in case of a subtree configured on the last line of .snmprec file.

  • Fix to line separator character used in file logger – now it’s platform-dependent.

Revision 0.2.1, released on Apr 07, 2013#

  • WARNING: this release brings some backward incompatibilities in

    • variation modules names and options

    • community names (in Windows platform)

    • stock variation modules installation location

    • sql module OID format stored in database

    Please read the changes below for more information.

  • License updated to vanilla BSD 2-Clause (

  • Variation modules can now participate in .snmprec production what can be used for capturing additional information about SNMP Agent being snapshotted in .snmprec files. The following changes have been made to the system:

    • the tool can be passed variation module name.

    • variation modules can now define the ‘record’ callable which will be given a chance to influence snmprec record being written.

    • existing ‘process’ callable in variation modules renamed into ‘variate’ for clarity.

    • variation modules’ init() and shutdown() methods accept **context, ‘mode’ parameter being passed indicating current operation mode.

    • variation modules running in recording mode can communicate to the upper levels that they either won’t produce any data on the current invocation or request another round of SNMP Agent walk.

  • Variation modules options now take shape of a key-value pairs. This might break backward compatibility with 0.2.0!

  • The and variation modules merged into a single module which also supports INTEGER&TIMETICKS values as well as recording feature.

  • The and modules merged into a single module which also supports SET value verification against per-OID access list.

  • The variation module extended to support variation based on SET value.

  • The variation module extended to support variation based on SET value and time of date.

  • Format of the OID stored in SQL database changed in a backward incompatible manner.

  • Recording functionality added to the and modules.

  • The new “multiplex” variation module added to be able to record and replay a sequence of .snmprec files ordered by time.

  • SNMP GETBULK operation is now supported by

  • Redesign of grammar objects – the new concept is that they are only responsible for basic record layout, fields normalization. and SNMP types resolution. However complex field formatting (such as grammar-specific tag modifiers) is now up to higher-level ‘Record’ objects.

  • Simulator-generated community names now uses ‘/’ as path separator regardless of the platform. This allows for unified Simulator view in terms of community and context names across the platforms.

  • Snapshot files recording now works under Python3.

  • Install data and variation modules into package root to make easy_install work again. Search these directories at runtime as a last resort - prefer system or home locations as it is more natural to keep changing data there.

  • Simulator is now more tolerant to duplicate variation modules (just ignores recently found) and catches duplicate data files (also ignores more recent).

  • On Windows, search both data and variation modules into %PROGRAMFILES%

Revision 0.2.0, released on Mar 12, 2013#

  • Major overhaul aimed at adding value variation features to the Simulator core:

    • data files may now hold not only terminal OIDs but also OID subtrees

    • pluggable value variation modules interfaces and basic modules added

    • write support added through the use of appropriate variation modules

    • SQL backend for keeping and modifying SNMP snapshots added in form of a value variation module

    • subprocess execution variation module added what could be used for external process invocation on SNMP request to Simulator

    • SNMP Notification Originator variation module added what could be used for sending SNMP TRAP/INFORM messages to SNMP entities on SNMP requests to Simulator

  • SNMP snapshots now being called ‘data files’ rather than ‘device files’ which is a legacy term.

  • Data files and variation modules are now installed into platform-specific directories.

  • Data files and variation modules are now looked up at several, platform-specific, locations including $HOME/.snmpsim

  • Simulator data files indices are now created and kept in a dedicated temporary directory which is also configurable though snmpsimd command-line.

  • Example data files simplified, more native and foreign snapshots added.

  • Fix to not to record end-of-mib.

  • Fix to py2exe settings of

Revision 0.1.6, released on Jan 30, 2013#

  • Net-SNMP’s .snmpwalk files created with the “snmpwalk -ObentU” command can now be used by the Simulator directly.

  • SimpleAgentPro’s .sapwalk files support added to Simulator.

  • Fixes to –start-oid & –stop-oid params to make the working again.

  • Simulator reports supported device files types on startup.

  • Shared device files now supported. Snapshots can now be indicated as shared through a symbolic link. Managers can use different credentials to access and modify the same set of Managed Objects.

Revision 0.1.5, released on Aug 23, 2012#

  • Simulator device file selection by a combination of ContextName, Transport ID and source address implemented.

  • Rudimentary MIB write support added (snmpset now works). Still need to support MIB-defined constraints.

  • Fix to to ignore possibly missing .dbm file on failed index rebuild.

  • Fix to OID search code what used to always pick the first OID in file while looking for EOL (Python3 only).

Revision 0.1.4, released on Jul 25, 2012#

  • Simulator device file selection by a combination of Community, Transport ID and source address implemented (for –v2c-arch mode).

  • UDP/IPv6 and UNIX domain socket transports support added to and tools.

  • The and tools now support additional SNMPv3 authentication (SHA) and encryption (3DES, AES192, AES256) algorithms provided by pysnmp.

  • Simulator now supports binding to and listening at multiple local endpoints. The –agent-address & –agent-port options are now obsolete.

  • The tool Agent address specification syntax unified with that of

  • Multiple –device-dir c/l options are now supported by

  • Some runtime diagnostics added to

  • The tool unconditionally rebuilds existing indices of unknown format.

  • Device files handling indexing made faster by not calling <fileobj>.tell(). That also required opening files in ‘binary’ mode to make sure offset calculation will work correctly.

  • Attempt to open DBM in “fast” and “unsync” modes when building indices to speed-up index generation.

  • Package meta information updated.

  • Fix to to make SNMP debugging working again.

  • Fix to to properly support non-default SNMP context name.

  • Fix to infinite loop possibly occurring at OID search routine.

  • Fix to DBM key type (string vs byte issue)

  • Fix to MIB path handling.

  • Fix to index object to make “snmpwalk -c index” work again.

  • Fix to index object registration in –v2c-arch mode.

  • Fix to SNMPv2 exception objects translation into SNMPv1 PDU in the –v2c-arch mode

Revision 0.1.3, released on Nov 12, 2011#

  • Initial revision of the tool.

  • Some more MIB-originated device files added.

Revision 0.1.2, released on Nov 09, 2011#

  • Some more py2k refactoring (some features did not work otherwise).

  • Fix to values tags matching at (simulator did not work otherwise).

  • Fixes to sys.exc_info invocation.

Revision 0.1.1, released on Nov 06, 2011#

  • Major overhaul for Python 2.4 – 3.2 compatibility: + drop explicit long integer type use + map()/filter() replaced with list comprehension + apply() replaced with */**args + dictionary operations made 2K/3K compatible + division operator made 2K/3K compatible + exception syntax made 2K/3K compatible + tuple function arguments resolved to scalars to become py3k compatible

Revision 0.0.10, released on Dec 31, 2010#

  • –agent-port handling bug fixed in

  • –v3-arch command-line flag added to save on large number of [expensive] addV1System() calls.

  • setuptools dependencies improved

Revision 0.0.9, released on Dec 21, 2010#

  • Simulator now builds a table of loaded device files in a dedicated ‘index’ context.

  • Use OS-specific file extension separator for better portability.

  • Support .db extensions voluntarily added by gdbm on OS X.

  • Fix to null-typed value read from .dump device file.

  • Legacy SNMPv1/v2c community string generation policy dropped.

  • SNMPv3 VACM initialization dropped altogether, as the specialized SMI backend used by Simulator does not implement access control.

  • Fix to support zero-length device files.

  • Ignore value syntax errors in device files occurred when responding.

  • Optionally validate device file data while indexing.

  • Allow forced device files re-indexing.

  • Fix to broken IP address serialization code in recorder.

Revision 0.0.8, released on Dec 10, 2010#

  • Initial public release.