Cisco IE 4000, Руководство по настройке программного обеспечения

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Configuring Embedded Event Manager
Information About Embedded Event Manager
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Generating an SNMP trap.
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Generating prioritized syslog messages.
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Reloading the Cisco IOS software.
Embedded Event Manager Policies
EEM can monitor events and provide information, or take corrective action when the monitored events occur or a
threshold is reached. An EEM policy is an entity that defines an event and the actions to be taken when that event occurs.
There are two types of EEM policies: an applet or a script. An applet is a simple policy that is defined within the CLI
configuration. It is a concise method for defining event screening criteria and the actions to be taken when that event
occurs. Scripts are defined on the networking device by using an ASCII editor. The script, which can be a bytecode (.tbc)
and text (.tcl) script, is then copied to the networking device and registered with EEM. You can also register multiple
events in a .tcl file.
Cisco enhancements to TCL in the form of keyword extensions facilitate the development of EEM policies. These
keywords identify the detected event, the subsequent action, utility information, counter values, and system information.
For complete information on configuring EEM policies and scripts, see Embedded Event Manager Configuration Guide,
Cisco IOS Release 15M&T .
Embedded Event Manager Environment Variables
EEM uses environment variables in EEM policies. These variables are defined in an EEM policy tool command language
(TCL) script by running a CLI command and the
event manager environment command.
User-defined variables
Defined by the user for a user-defined policy.
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Cisco-defined variables
Defined by Cisco for a specific sample policy.
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Cisco built-in variables (available in EEM applets)
Defined by Cisco and can be read-only or read-write. The read-only variables are set by the system before an applet
starts to execute. The single read-write variable, _exit_status, allows you to set the exit status for policies triggered
from synchronous events.
Cisco-defined environment variables and Cisco system-defined environment variables might apply to one specific event
detector or to all event detectors. Environment variables that are user-defined or defined by Cisco in a sample policy are
set by using the
event manager environment global configuration command. You must defined the variables in the EEM
policy before you register the policy.
For information about the environmental variables that EEM supports, see Embedded Event Manager Configuration
Guide, Cisco IOS Release 15M&T .
EEM 3.2
EEM 3.2 introduces these event detectors:
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Neighbor Discovery—Provides the ability to publish a policy to respond to automatic neighbor detection when:
— a Cisco Discovery Protocol (CDP) cache entry is added, deleted, or updated.
— a Link Layer Discovery Protocol (LLDP) cache entry is added, deleted or updated.