Users Guide

Security Commands 1033
User Guidelines
RADIUS servers are keyed by the host name/IP address, therefore it is
advisable to use unique server host names. Use the show aaa servers
{accounting|authentication} command to display the hostname/IP address
to list name mapping.
Multiple authentication servers may be configured with the same name using
the name command.
Dell EMC Networking implements a two-level hierarchy for RADIUS servers.
The top level is a list of servers which is alphabetically ordered by name. Each
server within the top level may be associated with the multiple server
hostnames/IP addresses. When multiple RADIUS servers are configured with
different names (for example, one server is name1 with address 1.1.1.1 and
the second server is name2 with address 1.1.1.2):
• The RADIUS request is always sent to the first server in the alphabetically
ordered list of servers, for example, server name1 is attempted before
moving on to the server name 2 server. Even if the priority value of hosts/IP
addresses in server name 2 is lower (a lower value indicates a higher
priority), the request would be sent to server name 1. If, for the server
name 1, all the configured hostnames/IP addresses fail to respond, the
request is sent to the second configured server.
• Within a server, the primary server is always tried first. Use the primary
command in RADIUS Server configuration mode to designate a primary
server. One can have multiple secondary hostnames/IP addresses in the
same server list. From the multiple secondary hostnames/IP addresses, the
one with the lowest priority value is tried first. In a server with multiple
hostnames/IP addresses with the same priority, the order of attempts is
based on lexicographic order. For example, if hostnames name9, name1,
name6 are configured as secondary hosts, the hostnames are attempted in
the order name1, name6, name9 when the primary host fails to respond.
Command History
Updated syntax in version 6.5 firmware.
Example
The following example specifies a RADIUS authentication server with the
following characteristics: