SNMP MIB parser
PySMI is a pure-Python implementation of SNMP SMI MIB parser. This tool is designed to turn ASN.1 MIBs into various formats. As of this moment, JSON and pysnmp modules can be generated from ASN.1 MIBs.
Features
- Understands SMIv1, SMIv2 and de-facto SMI dialects
- Turns MIBs into pysnmp classes and JSON documents
- Maintains an index of MIB objects over many MIB modules
- Automatically pulls ASN.1 MIBs from local directories, ZIP archives, HTTP and FTP servers
- 100% Python, requires Python 3.10 or newer
How to use PySMI
If you are using pysnmp, you might never notice pysmi presence - pysnmp calls pysmi for MIB download and compilation behind the scenes (you can still can do that manually by invoking mibdump tool).
To turn ASN.1 MIB into a JSON document, call mibdump tool like this:
$ mibdump --generate-mib-texts --destination-format json IF-MIB
Source MIB repositories: https://pysnmp.github.io:443/mibs/asn1/@mib@
Borrow missing/failed MIBs from:
Existing/compiled MIB locations:
Compiled MIBs destination directory: /home/you/.pysnmp/mibs
MIBs excluded from code generation:
MIBs to compile: IF-MIB
Destination format: json
Parser grammar cache directory: not used
Also compile all relevant MIBs: yes
Search pysmi's bundled base MIBs, newest revision winning: yes
Prefer --mib-source where no revision decides: no
Base MIBs eligible to be written out from the bundle: RFC-1212, RFC-1215, RFC1065-SMI, RFC1155-SMI, RFC1158-MIB, RFC1213-MIB, SNMPv2-CONF, SNMPv2-SMI, SNMPv2-TC, SNMPv2-TM
Rebuild MIBs regardless of age: no
Prune stored MIBs with no remaining source: no
Dry run mode: no
Create/update MIBs: yes
Byte-compile Python modules: no (optimization level no)
Report a failed MIB as an error: yes
Generate OID->MIB index: no
Generate texts in MIBs: yes
Keep original texts layout: no
Try various file names while searching for MIB module: yes
Created/updated MIBs: IANAifType-MIB, IF-MIB, SNMPv2-CONF, SNMPv2-MIB, SNMPv2-SMI, SNMPv2-TC
Pre-compiled MIBs borrowed:
Up to date MIBs:
Missing source MIBs:
Omitted MIBs (they import a failed MIB):
Repaired MIBs:
MIBs found in more than one source:
Failed MIBs:
The Borrow missing/failed MIBs from: line is empty because there is no
default borrower. Pass --mib-borrower to use the feature; the trees pysmi
used to default to were compiled pysnmp modules, and those were withdrawn for
the reason the MIB distribution
gives.
JSON document build from IF-MIB module would hold information such as:
{
"ifMIB": {
"name": "ifMIB",
"oid": "1.3.6.1.2.1.31",
"class": "moduleidentity",
"revisions": [
"2007-02-15 00:00",
"1996-02-28 21:55",
"1993-11-08 21:55"
]
},
...
"ifTestTable": {
"name": "ifTestTable",
"oid": "1.3.6.1.2.1.31.1.3",
"nodetype": "table",
"class": "objecttype",
"maxaccess": "not-accessible"
},
"ifTestEntry": {
"name": "ifTestEntry",
"oid": "1.3.6.1.2.1.31.1.3.1",
"nodetype": "row",
"class": "objecttype",
"maxaccess": "not-accessible",
"augmention": {
"name": "ifTestEntry",
"module": "IF-MIB",
"object": "ifEntry"
}
},
"ifTestId": {
"name": "ifTestId",
"oid": "1.3.6.1.2.1.31.1.3.1.1",
"nodetype": "column",
"class": "objecttype",
"syntax": {
"type": "TestAndIncr",
"class": "type"
},
"maxaccess": "read-write"
},
...
}
In general, converted MIBs capture all aspects of original (ASN.1) MIB contents and layout. The snippet above is just a partial example, but here is the complete IF-MIB.json file.
Besides one-to-one MIB conversion, PySMI library can produce JSON index to facilitate fast MIB information lookup across large collection of MIB files. For example, JSON index for IP-MIB.json, TCP-MIB.json and UDP-MIB.json modules would keep information like this:
{
"compliance": {
"1.3.6.1.2.1.48.2.1.1": [
"IP-MIB"
],
"1.3.6.1.2.1.49.2.1.1": [
"TCP-MIB"
],
"1.3.6.1.2.1.50.2.1.1": [
"UDP-MIB"
]
},
"identity": {
"1.3.6.1.2.1.48": [
"IP-MIB"
],
"1.3.6.1.2.1.49": [
"TCP-MIB"
],
"1.3.6.1.2.1.50": [
"UDP-MIB"
]
},
"oids": {
"1.3.6.1.2.1.4": [
"IP-MIB"
],
"1.3.6.1.2.1.5": [
"IP-MIB"
],
"1.3.6.1.2.1.6": [
"TCP-MIB"
],
"1.3.6.1.2.1.7": [
"UDP-MIB"
],
"1.3.6.1.2.1.49": [
"TCP-MIB"
],
"1.3.6.1.2.1.50": [
"UDP-MIB"
]
}
}
With this example, compliance and identity keys point to MODULE-COMPLIANCE and MODULE-IDENTITY MIB objects, oids list top-level OIDs branches defined in MIB modules.
The published distribution no longer carries a JSON index of its own. What it
publishes is index-v2.csv, OID
to module, and core.db, which answers per node rather than per module — see
the MIB distribution.
The PySMI library can automatically fetch required MIBs from HTTP, FTP sites or local directories. You could configure any MIB source available to you (including the MIB distribution) for that purpose.
How to get PySMI
The pysmi package is distributed under terms and conditions of 2-clause BSD license. Source code is freely available as a GitHub repo.
Run uv add pysnmp-pysmi or pip install pysnmp-pysmi, or download it from
PyPI. Note the name: pysmi is the original,
unmaintained package.
To try the command-line tools without installing anything permanently:
$ uvx --from pysnmp-pysmi mibdump --help
How to develop PySMI
PySMI uses uv for dependency management, builds and releases.
$ uv sync # create .venv and install everything, including dev tools
$ uv run pytest # run the test suite
$ uv run mibdump --help
Linting, formatting and type checking are run through pre-commit, which is what CI checks:
$ uv run pre-commit install # optional, to run these on every commit
$ uv run pre-commit run --all-files
That covers ruff for linting and formatting, and mypy for type checking. To build the documentation:
$ uv run sphinx-build -b html docs/source docs/build
If something does not work as expected, open an issue at GitHub or post your question on Stack Overflow.
Copyright (c) 2015-2020, Ilya Etingof. Copyright (c) 2024-2026, the PySNMP maintainers. All rights reserved.
4 maintainers
Release files for pysnmp-pysmi 4.1.1
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| pysnmp_pysmi-4.1.1.tar.gz | 4.5 MB | Details |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| pysnmp_pysmi-4.1.1-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 7.6 MB
Release files / pysnmp_pysmi-4.1.1.tar.gz
| Download URL | pysnmp_pysmi-4.1.1.tar.gz |
|---|---|
| Size | 4.5 MB |
| Tags | Source |
|
SHA-256 checksum How to use checksums |
dcd364d9d1a23320ed971008c8800baf09027486f857dec2cc574a25afc9ddbf
|
|
BLAKE2b-256 checksum How to use checksums |
064ba5e9bc97a431426b27b348d36f02cc51a571570f5cc7a12b53f28b7fbaa7
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/7.0.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Sep 11, 2026.
Transparency logRelease files / pysnmp_pysmi-4.1.1-py3-none-any.whl
| Download URL | pysnmp_pysmi-4.1.1-py3-none-any.whl |
|---|---|
| Size | 3.2 MB |
| Tags | Python 3 |
|
SHA-256 checksum How to use checksums |
33b436c0bf8d186fb9613fc3365fe784c252b2bd22442ea16fa5d874fc14b270
|
|
BLAKE2b-256 checksum How to use checksums |
c55b94231f6aa9ee8343a5802bff43f1a41d7bae0dfc1ea8574fdc47ad305a84
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/7.0.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Sep 11, 2026.
Transparency log
