Взято с http://www.cisco.com/en/US/docs/ios/csa/configuration/guide/csa_commands.html
Command or Action
Obtain the PAK.
The PAK is provided to you when you order or purchase the right to use a feature set for a particular platform.
•The PAK serves as a receipt and is used as part of the process to obtain a license.
Enables privileged EXEC mode.
•Enter your password if prompted.
show license udi
Router# show license udi
Displays all the UDI values that can be licensed in a system.
•You need the UDI of the device as part of the process to obtain a license.
Convert the PAK to a license by entering the PAK and the UDI into the Cisco Product License Registration portal:http://www.cisco.com/go/license.
After entering the appropriate information, you will receive an e-mail containing the license information that you can use to install the license:
•Copy the license file received from the Cisco Product License Registration portal to the appropriate file system on the device.
•Click the Install button on the web page.
license install stored-location-url
Router# license install tftp://infra-sun/<user>/license/5400/38a.lic
Installs the license.
•Accept the end-user license agreement if prompted.
(Optional) Restarts the device to enable the new feature set.
где UDI Product ID - это CISCO881-K9