Configuring the Switch
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Configuring Local/Remote Logon Authentication
Use the Authentication Settings menu to restrict management access based on
specified user names and passwords. You can manually configure access rights on
the switch, or you can use a remote access authentication server based on RADIUS
or TACACS+ protocols.
Remote Authentication Dial-in
User Service (RADIUS) and
Terminal Access Controller
Access Control System Plus
(TACACS+) are logon
authentication protocols that use
software running on a central
server to control access to
RADIUS-aware or TACACS-
aware devices on the network.
An authentication server contains
a database of multiple user name/password pairs with associated privilege levels for
each user that requires management access to the switch.
RADIUS uses UDP while TACACS+ uses TCP. UDP only offers best 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.
Command Usage
• By default, management access is always checked against the authentication
database stored on the local switch. If a remote authentication server is used, you
must specify the authentication sequence and the corresponding parameters for
the remote authentication protocol. Local and remote logon authentication control
management access via the console port, web browser, or Telnet.
• RADIUS and TACACS+ logon authentication assign a specific privilege level for
each user name/password pair. The user name, password, and privilege level
must be configured on the authentication server.
• You can specify up to three authentication methods for any user to indicate the
authentication sequence. For example, if you select (1) RADIUS, (2) TACACS and
(3) Local, the user name and password on the RADIUS server is verified first. If the
RADIUS server is not available, then authentication is attempted using the
TACACS+ server, and finally the local user name and password is checked.
Command Attributes
• Authentication – Select the authentication, or authentication sequence required:
- Local – User authentication is performed only locally by the switch.
- Radius – User authentication is performed using a RADIUS server only.
- TACACS – User authentication is performed using a TACACS+ server only.
- [authentication sequence] – User authentication is performed by up to three
authentication methods in the indicated sequence.
Web
Telnet
RADIUS/
TACACS+
server
console
1. Client attempts management access.
2. Switch contacts authentication server.
3.Authenticationserverchallengesclient.
4. Client responds with proper password or key.
5.Authenticationserverapprovesaccess.
6. Switch grants management access.