Throttling Of Radius Records - Cisco ASR 9000 Series Configuration Manual

Configuring Authentication, Authorization, and Accounting Functions
Command or Action

Throttling of RADIUS Records

The Throttling of AAA (RADIUS) records is a mechanism to avoid RADIUS congestion and instability. This
function is useful in situations when there is insufficient bandwidth to accommodate a sudden burst of AAA
requests generated by the BNG for the RADIUS server.
While configuring throttling, a threshold rate, which corresponds to the maximum number of outstanding
requests, is defined. It is possible to configure independent throttling rates for access (authentication and
authorization) and accounting requests. After a threshold value is reached for a server, no further requests of
that type are sent to the server. However, for the pending requests, a retransmit timer is started, and if the
outstanding request count (which is checked after every timer expiry), is less than the threshold, then the
request is sent out.
As a session may timeout due to throttle on the access requests, a limit is set for the number of retransmit
attempts. After this limit is reached, further access requests are dropped. Throttled accounting requests,
however, are processed through the server-group failover process.
The throttling feature can be configured globally, or for a server-group. However, the general rule of
configuration preference is that the server-group configuration overrides global configuration, if any.
The syntax for the throttling CLI command is:
radius-server throttle {[accounting THRESHOLD] [access THRESHOLD [access-timeout
NUMBER_OF-TIMEOUTS]]}
where:
• accounting THRESHOLD—Specifies the threshold for accounting requests. The range is from 0 to
• access THRESHOLD—Specifies the threshold for access requests. The range is from 0 to 65536. The
• access-timeout NUMBER_OF-TIMEOUTS—Specifies the number of consecutive timeouts that must
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65536. The default is 0, and indicates that throttling is disabled for accounting requests.
default is 0, and indicates that throttling is disabled for accounting requests.
occur on the router, after which access-requests are dropped. The range of is from 0 to 10. The default
is 3.
Cisco ASR 9000 Series Aggregation Services Router Broadband Network Gateway Configuration Guide, Release
Purpose
end—Prompts user to take one of these actions:
• Yes— Saves configuration changes and exits the configuration
session.
• No—Exits the configuration session without committing the
configuration changes.
• Cancel—Remains in the configuration mode, without
committing the configuration changes.
Throttling of RADIUS Records
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