towerops/priv/mibs

SNMP MIB Files

This directory contains SNMP MIB (Management Information Base) files used by Towerops for network device monitoring.

Directory Structure

• standard/ - Standard IETF/IANA MIBs (IF-MIB, ENTITY-MIB, etc.)
• cisco/ - Cisco vendor-specific MIBs
• mikrotik/ - MikroTik vendor-specific MIBs
• net-snmp/ - Net-SNMP specific MIBs (LM-SENSORS, UCD-SNMP)

Source

MIB files are sourced from the LibreNMS project, which maintains a comprehensive collection of vendor MIBs.

Purpose

These MIB files serve as:

1. Reference Documentation - Authoritative source for OID definitions
2. Validation - Tests verify that hardcoded OIDs in profile modules match MIB definitions
3. Discovery - Can be browsed to understand available SNMP objects

Usage in Code

Profile modules (e.g., Towerops.Snmp.Profiles.Cisco) contain hardcoded OID strings for performance. These are validated against MIB files during testing to ensure accuracy.

Example from Towerops.Snmp.Profiles.Base:

@interface_oids %{
  if_index: "1.3.6.1.2.1.2.2.1.1",  # Validated against IF-MIB
  if_descr: "1.3.6.1.2.1.2.2.1.2"   # Validated against IF-MIB
}

Adding New MIBs

To add support for a new vendor:

1. Create a directory: priv/mibs/vendor_name/
2. Download MIB files from LibreNMS or vendor
3. Add OID references in the appropriate profile module
4. Tests will automatically validate against the new MIBs

MIB File Format

MIB files use ASN.1 (Abstract Syntax Notation One) format, which defines:

• Object identifiers (OIDs)
• Data types
• Access levels
• Descriptions

Testing

See test/towerops/snmp/mib_validation_test.exs for OID validation tests.