Juniper JUNOSE 11.1.X - BROADBAND ACCESS CONFIGURATION GUIDE 6-4-2010 Configuration Manual page 75

NOTE: After the fourth retransmission, the configured timeout value is ignored, and
the router uses a backoff algorithm that increases the timeout between each
succeeding transmission. The router used the backoff algorithm only for subscriber
AAA accounting messages except for Acct-On messages.
The backoff algorithm is:
NOTE: When a RADIUS server times out or when it has no available RADIUS identifier
values, the router removes the RADIUS server from the list of available servers for
a period of time. The router restores all configured servers to the list if it is about to
remove the last server. Restoring the servers avoids having an empty server list.
udp-port
Use to set the number of seconds (1–1000) before the router retransmits a
RADIUS packet to an authentication or accounting server.
If the interval is reached and there is no response from the primary RADIUS
authentication or accounting server, the router attempts another retry. When
the retry limit is reached, the client sends the request to the secondary server.
When the retry limit for the secondary server is reached, the router attempts to
reach the tertiary server, and so on.
Example
host1(config)#radius authentication server 10.10.0.1
host1(config-radius)#timeout 5
Use the no version to restore the default value, 3 seconds.
See timeout
Use to configure the UDP port on the router where the RADIUS authentication,
accounting, preauthentication, and route-download servers reside. The router
uses this port to communicate with the RADIUS authentication servers.
Specify a port number in the range 0–65536. For authentication,
preauthentication, or route-download servers, the default UDP port is 1812. For
accounting servers, the default is 1813.
For an accounting server, specify a port number in the range 0–65536. The
default is 1813.
Example
host1(config)#radius authentication server 10.10.9.1
host1(config-radius)#udp-port 1645
Configuring RADIUS Authentication and Accounting Servers
Chapter 1: Configuring Remote Access
35