HP Cisco Nexus 5000 Cisco Nexus 5000 Series and Cisco Nexus 2000 Series MIB Qu - Page 4

MIBs and Network Management Send documentation comments to [email protected] • Tables, page 4 • SYNTAX Clause, page 5 • MAX-ACCESS Clause, page 5 • AGENT-CAPABILITIES, page 6 Object Identifiers The MIB structure is logically represented by a tree hierarchy. The root of the tree is unnamed and splits into three main branches: Consultative Committee for International Telegraph and Telephone (CCITT), International Organization for Standardization (ISO), and joint ISO/CCITT. These branches and those branches that fall below each category have short text strings and integers to identify them. Text strings describe object names, while integers allow the computer software to create compact, encoded representations of the names. Each MIB variable is assigned with an object identifier. The object identifier is the sequence of numeric labels on the nodes along a path from the root to the object. For example, the MIB variable tftpHost is indicated by the number 1. The object identifier for tftpHost is iso.org.dod.internet.private.enterprise.cisco.workgroup products.stack group.tftp group.tftpHost or .1.3.6.1.4.1.9.5.1.5.1. The last value is the number of the MIB variable tftpHost. Tables When network management protocols use names of MIB objects in messages, each name has an appended suffix. This suffix is called an instance identifier. It identifies one occurrence of the associated MIB object. For simple scalar objects, the instance identifier 0 refers to the instance of the object with that name (for example, sysUpTime.0). A MIB can also contain tables of related objects. For example, ifOperStatus is a MIB object inside the ifTable from the IF-MIB. It reports the operational state for an interface on a switch. Because switches may have more than one interface, it is necessary to have more than one instance of ifOperStatus. This instance value is added to the end of the MIB object as the instance identifier (for example, ifOperStatus.2 reports the operational state for interface number 2). Each object in a table is constructed with a set of clauses defined by the SMI. These clauses include the SYNTAX clause, MAX-ACCESS clause, STATUS clause, and DESCRIPTION clause. An excerpt of the information in the VSAN table (known as vsanTable) from CISCO-VSAN-MIB follows: vsanTable OBJECT-TYPE SYNTAX SEQUENCE OF VsanEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A table of VSANs configured on this device." ::= { vsanConfiguration 3 } vsanEntry OBJECT-TYPE SYNTAX VsanEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry (conceptual row) in the vsanTable." INDEX { vsanIndex } ::= { vsanTable 1 } VsanEntry ::= SEQUENCE { vsanIndex VsanIndex, Cisco Nexus 5000 Series and CiscoNexus 2000 Series MIB Quick Reference 4 OL-16784-01