Figure C-1 shows the top layers of the standard MIB tree. The root layer is unnamed. All MIB variables that are useful for network management are located under the internet subtree . Following the tree structure downward, internet is referenced as OID iso. org. dod. internet, or 1.3.6.1. Figure C-1. Top-Level MIB Structure
The iso. org. dod. internet. mgmt subtree (1.3.6.1.2) contains many useful objects, all organized under the mib subtree (1.3.6.1.2.1). These objects fall into the following categories:
The experimental (1.3.6.1.3) subtree can contain MIBs that are new and experimental in nature. However, experimental MIBs can also be introduced into the standard mib subtree (1.3.6.1.2). The private (1.3.6.1.4) subtree contains one subtree, enterprise (1.3.6.1.4.1), where all network vendor-specific objects are located. The Cisco private MIB structure is contained in the cisco subtree (1.3.6.1.4.1.9). The set of specific MIBs that are included under the cisco MIB tree varies according to the hardware platform and the IOS software release level. A good resource for referencing and downloading MIBs is the Cisco MIBs page on CCO:
Through the tools offered , you can do the following:
TIP You can also use the undocumented show snmp mib command to see a list of MIB objects that are available on a router. Although this command lists the objects in a short format (without OIDs), it can be useful to find the names of specific MIB variables. |