A Management Information Base (MIB) file contains information used to manage entities in a network. This information is accessed by a protocol such as Simple Network Management Protocol (SNMP).
Every managed device and SNMP equipment vendor in the network maintains values in the MIB. Object Identifiers (OIDs) uniquely identify each entity in the MIB hierarchy, which is typically depicted in a tree structure. Each branch of the tree has a number and a name, and the complete path from the top of the tree to the entity forms the name of that entity.
For example, the Enterprise MIB for OmniTI assigned by the Internet Assigned Numbers Authority is 1.3.6.1.4.1.19552. This is further subdivided by products. For example, Momentum (Ecelerity) has the MIB 1.3.6.1.4.1.19552.1.
Within Momentum (ecelerity), 1.3.6.1.4.1.19552.1.1 is defined as product information with further subdivisions as shown below:
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1.3.6.1.4.1.19552.1.1.1– string, Product Name (Ecelerity) -
1.3.6.1.4.1.19552.1.1.2– string, version (_EC_VER) -
1.3.6.1.4.1.19552.1.1.3– string, build date (DATE)
Warning
The per-domain metrics exposed via Momentum's OCC-MIB do not support the SNMP GETNEXT operation, which means that you can't walk domain statistics with programs such as snmpwalk. Therefore, to get per-domain statistics via SNMP, you must know in advance what domain to query. This is fine for monitoring known domains, but you can't use SNMP to get a snapshot of the mail queues.
For your convenience, the OMNITI-SNMP-MIB.txt file found in the /opt/msys/ecelerity/docs/ directory is reproduced in this appendix.
The per-domain MIB is defined as: 1.3.6.1.4.1.19552.1.2.L.A.B.C.S.G where A.B.C indicates the domain name, and L represents the length of that domain. For example, aol.com would be represented as:
7.97.111.108.46.99.111.109 7 a o l . c o m
In this case 7 indicates the length of 'aol.com'. The length and the binding identifier replace L.A.B.C in the MIB. G corresponds to the MTAGroupIndexID (see RFC 2789, MTA MIB). S represents the metric type. We define the following metrics:
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0: domain name
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1: receptions
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2: failures
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3: deliveries
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4: transient failures
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5: outbound connections
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6: active queue size
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7: delayed queue size
For more information about Mail Monitoring MIBs, see RFC2789.
The aol.com domain name would have the following entry on the default binding: 1.3.6.1.4.1.19552.1.2.7.97.111.108.46.99.111.109.0.1: string 'aol.com'.
The MTAGroupIndexID can be determined by using snmpwalk and subtracting 1 from last number of the desired binding. You can also use snmpwalk to get the MTAGroupIndexID in order to determine per-domain stats.
For example:
shell> /opt/msys/3rdParty/bin/snmpwalk -v1 -c public 10.79.20.132:8162 1.3.6.1.4.1.19552.1.3 SNMPv2-Example::enterprises.19552.1.3.1.1 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.1.2 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.1.3 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.1.4 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.2.1 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.2.2 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.2.3 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.2.4 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.3.1 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.3.2 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.3.3 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.3.4 = Counter32: 0 SNMPv2-Example::enterprises.19552.1.3.4.1 = STRING: "none/all" SNMPv2-Example::enterprises.19552.1.3.4.2 = STRING: "none/default" SNMPv2-Example::enterprises.19552.1.3.4.3 = STRING: "none/cdp" SNMPv2-Example::enterprises.19552.1.3.4.4 = STRING: "none/example"
In the output above, cdp and example are binding names. The MTAGroupIndexID of cdp is 2 because 2 is one less than the last number in SNMPv2-SMI::enterprises.19552.1.3.4.3.