A
UTHENTICATION
S
EQUENCE
22-7authentication enable
This command defines the authentication method and precedence to use
when changing from Exec command mode to Privileged Exec command
mode with the enable command (see page19-2). Use the no form to
restore the default.
Syntax
authentication enable {[local] [radius] [tacacs]}
no authentication enable
local - Use local password only.
radius - Use RADIUS server password only.
tacacs - Use TACACS server password.
Default Setting
Local
Command Mode
Global Configuration
Command Usage
RADIU S us es U DP w hile TACAC S+ u ses TCP. UD P on ly o ffer s be st
effort delivery, while TCP offers a connection-oriented transport.
Also, note that RADIUS encrypts only the password in the
access-request packet from the client to the server, while TACACS+
encrypts the entire body of the packet.
RADIUS and TACACS+ logon authentication assigns a specific
privilege level for each user name and password pair. The user name,
password, and privilege level must be configured on the authentication
server.
You can specify three authentication methods in a single command to
indicate the authentication sequence. For example, if you enter
authentication enable radius tacacs local,” the user name and
password on the RADIUS server is verified first. If the RADIUS
server is not available, then authentication is attempted on the
TACACS+ server. If the TACACS+ server is not available, the local
user name and password is checked.