MIBs

If there are two or more MIBs with the same name, the Trapd LAM uses the last read MIB and ignores any previous versions. It is important to ensure that there are no discrepancies like this as you could have undesired behavior in trap resolution.

If a MIB imports and references another MIB that cannot be found in $MOOGSOFT_HOME/etc/mibs, any definitions using that reference are not resolvable. In this scenario, the Trapd LAM logs the following warning message :

WARN: Import [SNMPv2-SMI] not found for Mib [NET-SNMP-MIB]

If the same name is used to identify two or more different OIDs, only the first entry is accepted. For example, if internet is defined twice in two different OIDs, the Trapd LAM only considers the first to be part of the MIB:

internet OBJECT IDENTIFIER ::= { dod 1 }
internet OBJECT IDENTIFIER ::= { dod 2 }
directory OBJECT IDENTIFIER ::= { internet 1 }

In this example, directory is considered to be {dod 1 internet 1}.

If a MIB maps the same OID to two or more different names, only the first definition is accepted. The Trapd LAM logs subsequent definitions with a warning message such as:

netSnmpModuleIDs OBJECT IDENTIFIER ::= { netSnmpEnumerations 1 }
snmpDomainsConflict OBJECT IDENTIFIER ::= { netSnmpEnumerations 1 }

In this example, { netSnmpEnumerations 1 } is defined twice under two different names so only the latest occurrence of { netSnmpEnumerations } is considered part of the MIB. Here is an example of an OID conflict warning log message:

WARN : OID Conflict: Full OID [1.3.6.1.4.1.8072.3.1] has conflicting names, Mib [NET-SNMP-MIB -> snmpDomainsConflict] & Mib [NET-SNMP-MIB -> netSnmpModuleIDs]

If the same OID is mapped to multiple names between two or more MIBs, the Trapd LAM only accepts the first definition. The Trapd LAM logs any subsequent definitions with a warning message:

WARN: OID Conflict: Full OID [1.3.6.1.4.1.42.1.1] has conflicting names, Mib [MIB-1 -> deviceTemperature] & Mib [MIB-2 -> deviceTemp]

If an object definition references a parent which is not defined or imported in the MIB, then that object is not resolvable. The Trapd LAM logs a warning message such as:

snmpDomainsConflict OBJECT IDENTIFIER ::= { snmpv3 1 }

In this example, snmpv3 has not been defined or imported, so snmpDomainsConflict cannot be resolved and Trapd LAM displays a log warning message:

WARN: Mib [NET-SNMP-MIB]:Unable to resolve and find SINGLE parent for Mib Object [snmpDomainsConflict ::= { snmpv3 1 }]

The DISPLAY-HINT clause instructs Trapd LAM how to display the hex string using the format: [digits]x[delimiter].

For example, an object with DISPLAY-HINT "1x_" for value of 9e3f4242 outputs as follows: 9E_3F_42_42

An object with DISPLAY-HINT "2x-" clause for the same value outputs as a string: 9E3F-4242.

A varbind with DISPLAY-HINT "1x:" and a value of 5cf9388e7dd4 outputs 5C:F9:38:8E:7D:D4.This is the expected output for a MAC address.

The DEFVAL definitions specify a hex type and also result in Trapd LAM outputting values as hex strings. The default format is 1x.

A DEFVAL definition specifies a hex type in the following format, normally followed by an upper or lower case 'h':

DEFVAL { '0000-ffff'h }
DEFVAL { ''H }

If both DISPLAY-HINT and DEFVAL define recognisable hex formats, the DISPLAY-HINT format is used. If neither DISPLAY-HINT or DEFVAL definition is correctly specified, the octet string values use the following logic:

If a Hex DISPLAY-HINT or a Hex type DEFVAL is supplied for a MIB object then the Trapd LAM outputs these values as hex strings, regardless of any syntax definitions. The Trapd LAM does not resolve or associate syntax definitions.