Cisco ASR 9000 Serie

and the body. The remaining parts of the policy are optional: environmental must defines, namespace import,
entry status, and exit status.
Figure 2: Tcl Policy Structure and Requirements
The start of every policy must describe and register the event to detect using an event_register Tcl command
extension. This part of the policy schedules the running of the policy. For a list of the available EEM
event_register Tcl command extensions, see the Embedded Event Manager Event Registration Tcl Command
Extensions, on page 94. The following example Tcl code shows how to register the event_register_timer
Tcl command extension:
::cisco::eem::event_register_timer cron name crontimer2 cron_entry $_cron_entry maxrun 240
The following example Tcl code shows how to check for, and define, some environment variables:
# Check if all the env variables that we need exist.
# If any of them does not exist, print out an error msg and quit.
if {![info exists _email_server]} {
set result \
"Policy cannot be run: variable _email_server has not been set"
error $result $errorInfo
}
if {![info exists _email_from]} {
set result \
"Policy cannot be run: variable _email_from has not been set"
error $result $errorInfo
}
if {![info exists _email_to]} {
set result \
"Policy cannot be run: variable _email_to has not been set"
error $result $errorInfo
)
The namespace import section is optional and defines code libraries. The following example Tcl code shows
how to configure a namespace import section:
namespace import ::cisco::eem::*
namespace import ::cisco::lib::*
The body of the policy is a required structure and might contain the following:
•
The event_reqinfo event information Tcl command extension that is used to query the EEM for
information about the detected event. For a list of the available EEM event information Tcl command
extensions, see the Embedded Event Manager Event Information Tcl Command Extension, on page
129.
Cisco ASR 9000 Series Aggregation Services Router System Monitoring Configuration Guide, Release 4.2.x
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Configuring and Managing Embedded Event Manager Policies
How to Write Embedded Event Manager Policies Using Tcl