NetNotes

Cisco IOS banner tokens

Since Cisco IOS Release 12.0(3)T there is an option to use tokens when configuring different types of banner messages on routers.  The tokens are replaced with the respective parameter value when the banner is displayed, and they can reference different parameters of the device and/or configuration.

The table below lists the possible tokens and their support in different banner messages:

Банер\token	motd	login	exec	incoming	slip-ppp	Description
$(hostname)	YES	YES	YES	YES	YES	Hostname of the device
$(domain)	YES	YES	YES	YES	YES	Domain
$(peer-ip)	NO	NO	NO	NO	YES	IP Address of the peer device
$(gate-ip)	NO	NO	NO	NO	YES	IP Address of the gateway
$(encap)	NO	NO	NO	NO	YES	Encapsulation type
$(encap-alt)	NO	NO	NO	NO	YES	Encapsulation shown as SL/IP instead of SLIP.
$(mtu)	NO	NO	NO	NO	YES	MTU
$(line)	YES	YES	YES	YES	NO	Number of the line hosting the incoming connection
$(line-desc)	YES	YES	YES	YES	NO	Description of the line hosting the incoming connection

Here’s an exmaple of using the $(hostname) token when configuring a login banner:

R1(config)#banner login # You are connected to $(hostname). Authorized users only! #

This option comes in quite handy in cases of a global rollout including banner configuration on multiple devices (using a tool for configuration management/automated rollout, such as Expect, or a commercial one such as CiscoWorks).

Tags: banner, banner tokens, cisco IOS