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Cisco IE 2000 Switch Software Configuration Guide
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Chapter 5 Configuring Cisco IOS Configuration Engine
Information About Configuring Cisco IOS Configuration Engine
The Cisco IOS agents initiate communication with Configuration Engine by using the appropriate
ConfigID and EventID. Configuration Engine maps the ConfigID to a template and downloads the full
configuration file to the switch.
Figure 5-2 shows a sample network configuration for retrieving the initial bootstrap configuration file
by using DHCP-based autoconfiguration.
Figure 5-2 Initial Configuration Overview
Incremental (Partial) Configuration
After the network is running, new services can be added by using the Cisco IOS agent. Incremental
(partial) configurations can be sent to the switch. The actual configuration can be sent as an event
payload by way of the event gateway (push operation) or as a signal event that triggers the switch to
initiate a pull operation.
The switch can check the syntax of the configuration before applying it. If the syntax is correc t, the
switch applies the incremental configuration and publishes an event that signals success to the
configuration server. If the switch does not apply the incremental configuration, it publishes an event
showing an error status. When the switch has applied the incremental configuration, it can write it to
NVRAM or wait until signaled to do so.
Synchronized Configuration
When the switch receives a configuration, it can defer application of the configuration upon receipt of a
write-signal event. The write-signal event tells the switch not to save the updated configuration into its
NVRAM. The switch uses the updated configuration as its running configuration. This ensures that the
switch configuration is synchronized with other network activities before s aving the configuration in
NVRAM for use at the next reboot.
TFTP
server
DHCP relay agent
default gatewayDistribution layer
Configuration
Engine
Access layer
switches
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DHCP
server
VWAN