Dell Brocade DCX, Configuration Manual

Page: 169 / 1436

BigIron RX Series Configuration Guide 97
53-1001810-01
Configuring RADIUS security
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5. The RADIUS server validates the device using a shared secret (the RADIUS key).
6. The RADIUS server looks up the username in its database.
7. If the username is found in the database, the RADIUS server validates the password.
8. If the password is valid, the RADIUS server sends an Access-Accept packet to the device,
authenticating the user. Within the Access-Accept packet are three Brocade vendor-specific
attributes that indicate:
•
The privilege level of the user
•
A list of commands
•
Whether the user is allowed or denied usage of the commands in the list
The last two attributes are used with RADIUS authorization, if configured.
9. The user is authenticated, and the information supplied in the Access-Accept packet for the
user is stored on the device. The user is granted the specified privilege level. If you configure
RADIUS authorization, the user is allowed or denied usage of the commands in the list.
RADIUS authorization
When RADIUS authorization takes place, the following events occur.
1. A user previously authenticated by a RADIUS server enters a command on the device.
2. The device looks at its configuration to see if the command is at a privilege level that requires
RADIUS command authorization.
3. If the command belongs to a privilege level that requires authorization, the device looks at the
list of commands delivered to it in the RADIUS Access-Accept packet when the user was
authenticated. (Along with the command list, an attribute was sent that specifies whether the
user is permitted or denied usage of the commands in the list.)
NOTE
After RADIUS authentication takes place, the command list resides on the BigIron RX. The
RADIUS server is not consulted again once the user has been authenticated. This means that
any changes made to the user’s command list on the RADIUS server are not reflected until the
next time the user is authenticated by the RADIUS server, and the new command list is sent to
the BigIron RX.
4. If the command list indicates that the user is authorized to use the command, the command is
executed.
RADIUS accounting
RADIUS accounting works as follows.
1. One of the following events occur on the device:
•
A user logs into the management interface using Telnet or SSH
•
A user enters a command for which accounting has been configured
•
A system event occurs, such as a reboot or reloading of the configuration file
2. The device checks its configuration to see if the event is one for which RADIUS accounting is
required.