Cisco Systems 3750E manual Hostname and DeviceID, Using Hostname, DeviceID, and ConfigID

Chapter 4 Configuring Cisco IOS CNS Agents

Understanding Cisco Configuration Engine Software

DeviceID

Each configured switch participating on the event bus has a unique DeviceID, which is analogous to the switch source address so that the switch can be targeted as a specific destination on the bus. All switches configured with the cns config partial global configuration command must access the event bus.

Therefore, the DeviceID, as originated on the switch, must match the DeviceID of the corresponding switch definition in the Configuration Engine.

The origin of the DeviceID is defined by the Cisco IOS hostname of the switch. However, the DeviceID variable and its usage reside within the event gateway adjacent to the switch.

The logical Cisco IOS termination point on the event bus is embedded in the event gateway, which in turn functions as a proxy on behalf of the switch. The event gateway represents the switch and its corresponding DeviceID to the event bus.

The switch declares its hostname to the event gateway immediately after the successful connection to the event gateway. The event gateway couples the DeviceID value to the Cisco IOS hostname each time this connection is established. The event gateway caches this DeviceID value for the duration of its connection to the switch.

Hostname and DeviceID

The DeviceID is fixed at the time of the connection to the event gateway and does not change even when the switch hostname is reconfigured.

When changing the switch hostname on the switch, the only way to refresh the DeviceID is to break the connection between the switch and the event gateway. Enter the no cns event global configuration command followed by the cns event global configuration command.

When the connection is re-established, the switch sends its modified hostname to the event gateway. The event gateway redefines the DeviceID to the new value.

Caution When using the Configuration Engine user interface, you must first set the DeviceID field to the hostname value that the switch acquires after–not before–you use the cns config initial global configuration command at the switch. Otherwise, subsequent cns config partial global configuration command operations malfunction.

Using Hostname, DeviceID, and ConfigID

In standalone mode, when a hostname value is set for a switch, the configuration server uses the hostname as the DeviceID when an event is sent on hostname. If the hostname has not been set, the event is sent on the cn=<value> of the device.

In server mode, the hostname is not used. In this mode, the unique DeviceID attribute is always used for sending an event on the bus. If this attribute is not set, you cannot update the switch.

These and other associated attributes (tag value pairs) are set when you run Setup on the Configuration Engine.

Note For more information about running the setup program on the Configuration Engine, see the Configuration Engine setup and configuration guide at this URL on Cisco.com: http://www.cisco.com/en/US/products/sw/netmgtsw/ps4617/products_installation_and_configuration_ guide_book09186a00803b59db.html

Catalyst 3750-E and 3560-E Switch Software Configuration Guide

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