Concept Guide

• Access-Accept — the RADIUS server authenticates the user.
• Access-Reject — the RADIUS server does not authenticate the user.
If an error occurs in the transmission or reception of RADIUS packets, you can view the error by enabling the debug radius command.
Transactions between the RADIUS server and the client are encrypted (the users’ passwords are not sent in plain text). RADIUS uses UDP
as the transport protocol between the RADIUS server host and the client.
For more information about RADIUS, refer to RFC 2865, Remote Authentication Dial-in User Service.
RADIUS Authentication
Dell EMC Networking OS supports RADIUS for user authentication (text password) at login and can be specied as one of the login
authentication methods in the aaa authentication login command.
When conguring AAA authorization, you can congure to limit the attributes of services available to a user. When you enable
authorization, the network access server uses conguration information from the user prole to issue the user's session. The user’s access
is limited based on the conguration attributes. RADIUS exec-authorization stores a user-shell prole and that is applied during user login.
You may name the relevant named-lists with either a unique name or the default name. When you enable authorization by the RADIUS
server, the server returns the following information to the client:
• Idle Time
• ACL Conguration Information
• Auto-Command
• Privilege Levels
After gaining authorization for the rst time, you may congure these attributes.
NOTE
: RADIUS authentication/authorization is done for every login. There is no dierence between rst-time login and
subsequent logins.
Idle Time
Every session line has its own idle-time. If the idle-time value is not changed, the default value of 30 minutes is used.
RADIUS species idle-time allow for a user during a session before timeout. When a user logs in, the lower of the two idle-time values
(congured or default) is used. The idle-time value is updated if both of the following happens:
• The administrator changes the idle-time of the line on which the user has logged in.
• The idle-time is lower than the RADIUS-returned idle-time.
ACL Conguration Information
The RADIUS server can specify an ACL. If an ACL is congured on the RADIUS server, and if that ACL is present, the user may be allowed
access based on that ACL.
If the ACL is absent, authorization fails, and a message is logged indicating this.
RADIUS can specify an ACL for the user if both of the following are true:
• If an ACL is absent.
• If there is a very long delay for an entry, or a denied entry because of an ACL, and a message is logged.
NOTE
: The ACL name must be a string. Only standard ACLs in authorization (both RADIUS and TACACS) are supported.
Authorization is denied in cases using Extended ACLs.
Security 195