User Manual
UMN:CLI
V8102
511
10.2.7.4
IGMP-Proxy IF Flap Discredit
IGMP IF is IGMP Proxy-enabled upstream or downstream interface that is used for IGMP
proxy implementation.
IGMP IF flap discredit function is intended to apply a traffic flow penalty in IGMP interface
due to its link down-up (Flap). All of IGMP IFs have 100 credit values by default.
An IGMP IF loses the specified credit value in case the flapping happens on this interface.
Therefore, the forwarding path for the flow must be recalculated, causing low multicast
forwarding performance.
Under the ECMP environment, if IGMP Proxy multi-uplink interface is load-balancing
mode, a multicast traffic flow is split across the multipath according to the priority based
on its credit unit value and configurations. The upstream interfaces with the largest credit
would get the highest proxy-service priority.
If IGMP Proxy multi-uplink interface is specified the priority mode, one upstream interface
of the highest priority based on its credit value, priority and vid handles a multicast traffic
flow.
IGMP IF flap discredit function has been designed to minimize such a path recalculation
caused by the IF flapping, which can increase the stability and quality for multicast ser-
vice. Using this function, the V8102 gives a discredit to a IGMP IF for every flapping time,
and then the IF is not selected as a forwarding path until its credit is regenerated.
IGMP Proxy IF flap discredit function is implemented with the following restrictions, so
you must keep them in mind before setting the related commands or parameters.
•
If you configure recover-interval value as 0, the decreased IGMP IF credit is not re-
covered.
•
If the credit unit becomes 0 because of the continuous flapping of IGMP IF, the
credit is not recovered until
clear ip igmp if flap discredit
command is configured.
To enable/disable the IGMP IF flap discredit function, use the following command.
Command
Mode
Description
ip igmp if flap discredit
Global
Enables the IGMP IF flap discredit. (default)
no ip igmp if flap discredit
Disables the IGMP IF flap discredit.
To specify the discredit value in case of IGMP IF flapping, use the following command.
Command
Mode
Description
ip igmp if flap discredit unit
<1-
50>
Global
Specifies the discredit value for the IF flapping and
decreases the credit unit as much as a specified value.
(default: 5)
no ip igmp if flap discredit unit
Deletes a configured discredit value.
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