Cisco Catalyst 2960 Series, Configuration Manual

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Cisco IOS CNS Agents
The CNS event agent feature allows the switch to publish and subscribe to events on the event bus and works
with the Cisco IOS CNS agent. These agents, embedded in the switch Cisco IOS software, allow the switch
to be connected and automatically configured.
Related Topics
Enabling the Cisco IOS CNS Agent, on page 416
Initial Configuration
When the switch first comes up, it attempts to get an IP address by broadcasting a Dynamic Host Configuration
Protocol (DHCP) request on the network. Assuming there is no DHCP server on the subnet, the distribution
switch acts as a DHCP relay agent and forwards the request to the DHCP server. Upon receiving the request,
the DHCP server assigns an IP address to the new switch and includes the Trivial File Transfer Protocol
(TFTP) server Internet Protocol (IP) address, the path to the bootstrap configuration file, and the default
gateway IP address in a unicast reply to the DHCP relay agent. The DHCP relay agent forwards the reply to
the switch.
The switch automatically configures the assigned IP address on interface VLAN 1 (the default) and downloads
the bootstrap configuration file from the TFTP server. Upon successful download of the bootstrap configuration
file, the switch loads the file in its running configuration.
The Cisco IOS CNS agents initiate communication with the Configuration Engine by using the appropriate
ConfigID and EventID. The Configuration Engine maps the Config ID to a template and downloads the full
configuration file to the switch.
The following figure shows a sample network configuration for retrieving the initial bootstrap configuration
file by using DHCP-based autoconfiguration.
Figure 43: Initial Configuration
Related Topics
Enabling an Initial Configuration for Cisco IOS CNS Agent, on page 418
Monitoring CNS Configurations, on page 427
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
412
Information About Configuring the Configuration Engine