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Cisco IE 2000 Switch Software Configuration Guide
OL-25866-01
Chapter 36 Configuring SNMP
Information About SNMP
SNMP ifIndex MIB Object Values
In an NMS, the IF-MIB generates and assigns an interface index (ifIndex) object value that is a unique
number greater than zero to identify a physical or a logical interface. When the switch rebo ots or the
switch software is upgraded, the switch uses this same value for the interface. For example, if the switch
assigns a port 2 an ifIndex value of 10003, this value is the same after the switch reboots.
The switch uses one of the values in Table 36-3 to assign an ifIndex value to an interface.
Note The switch might not use sequential values within a range.
Community Strings
You use the SNMP community string to define the relationship between the SNMP manager and the
agent. The community string acts like a password to permit access to the agent on the switch. Optionally,
you can specify one or more of these characteristics associated with the string:
An access list of IP addresses of the SNMP managers that are permitted to use the community string
to gain access to the agent
A MIB view, which defines the subset of all MIB objects accessible to the given community
Read and write or read-only permission for the MIB objects ac cessible to the community
SNMP Notifications
A trap manager is a management station that receives and processes traps. Traps are system alerts that
the switch generates when certain events occur. By default, no trap manager is defined, and no traps a re
sent. Switches running this Cisco IOS release can have an unlimited number of trap managers.
Note Many commands use the word traps in the command syntax. Unless there is an option in the command
to select either traps or informs, the keyword traps refers to traps, informs, or both. Use the snmp-server
host global configuration command to specify whether to send SNMP notifications as traps or informs.
Tab l e 36-3 ifIndex Values
Interface Type ifIndex Range
SVI 1–4999
EtherChannel 5001–5048
Physical (such as Gigabit Ethernet or SFP-module interfaces) based
on type and port numbers
10000–14500
Null 10501
Loopback and Tunnel 24567 +