Understanding MIBs

The management information base (MIB) is a database of monitored and managed information on an Extreme device. The MIB structure can be represented by a tree hierarchy. The root splits into three main branches: International Organization for Standardization (ISO), Consultative Committee for International Telegraph and Telephone (CCITT), and joint ISO/CCITT. These branches have short text strings and integers (OIDs) to identify them. Text strings describe object names, while integers allow software to create compact, encoded representations of the names.

Extreme MIB structure

Each MIB variable is assigned an object identifier (OID). The OID is the sequence of numeric labels on the nodes along a path from the root to the object. For example, as shown in the following figure, the sysDescr is:

1.3.6.1.2.1.1.1

The corresponding name is:

iso.org.dod.internet.mgmt.mib-2.system.sysDescr

1.3.6.1.2.1.47

The corresponding name is:

iso.org.dod.internet.mgmt.mib-2.entityMIB

The other branches are part of the standard MIBs, and the portions relevant to configuring SNMP on an Extreme device are referenced in the remainder of this chapter.

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Extreme MIB tree
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Access to MIB variables

You can use a MIB browser to access the MIB variables. All MIB browsers load MIBs and perform queries.

Once loaded, MAX-ACCESS provides access levels between the agent and management station. The access levels are described in the following table.

Table 1. MIB access levels
Access level Description
Not accessible/None You cannot read or write to this variable.
Read-create Specifies a tabular object that can be read, modified, or created as a new row in a table.
Read-only You can only monitor information.
Read-write You can read or modify this variable.
Accessible-to-notify You can read this information only through traps.

Extreme MIBs

The Extreme MIB is a set of variables that are private extensions to the Internet standard MIBs. The Extreme agents support many Internet-standard MIBs. These standard MIBs are defined in RFC publications. To find specific MIB information, examine the Extreme proprietary MIB structure and the standard RFC MIBs supported by Extreme.

Extreme MIB files

The Extreme MIB files are as follows:

Obtaining the Extreme MIBs

You can download the Extreme-specific MIB files required for this release from the downloads area of Extreme.com. To download the Extreme-specific MIBs from Extreme.com, you must have a user name and password. MIBs are located in the SLX-OS release folder on the portal.