Differences between suppress-time and report-suppress on an S series switch

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For S series switches, suppress-time and report-suppress are irrelevant.
The suppress-time parameter specifies the period during which the switch forwards only one Report/Leave message of the same multicast group after receiving a Query message. The report-suppress parameter is used to terminate Report messages from users and respond to the Query packets from routers.

Other related questions:
Functions of suppress-time on S series switches
For an S series switch, to protect an upstream Layer 3 device from attacks and reduce the loads on the Layer 3 device, a Layer 2 device can suppress repeated IGMP Report and IGMP Leave messages sent from users in a VLAN. The message suppression mechanism is as follows: - After receiving and forwarding an IGMP Report/Leave message, the Layer 2 device does not forward repeated MLD Report messages to the router port within the suppression time. - If the Layer 2 device receives an IGMP General Query message or Multicast-Address-Specific message within the suppression time, it does not suppress the first IGMP Report message sent in response to the General Query message. In addition, the Layer 2 device resets the suppression timer when receiving the first IGMP Report message. suppress-time is used to set the suppression time of Report/Leave messages. By default, the suppression time for IGMP Report/Leave messages is 10s. If the suppression time is set to 0, Report/Leave messages are not discarded. The suppression function applies only to IGMPv1 and IGMPv2 Report/Leave messages and is invalid for IGMPv3 Report/Leave messages.

Differences between traffic suppression and storm control on S series switches
For S series switches, the differences between traffic suppression and storm control are as follows: Traffic suppression aims at controlling traffic rates within an acceptable range to limit incoming and outgoing traffic on interfaces. If the rate of incoming broadcast, multicast, or unknown unicast packets on an interface exceeds the threshold, a switch discards the packets exceeding the threshold and only allows the packets within the threshold to pass through. Take traffic suppression of unknown unicast packets for example. Assume that the traffic suppression threshold of unknown unicast packets is 100 pps. That is, the switch allows only 100 packets to pass through within one second, and discards the excess packets. Within the next second, the switch also allows only 100 packets to pass through. If the rate of outgoing broadcast, multicast, or unknown unicast packets on an interface exceeds the threshold, the switch blocks all packets of this type. That is, the interface does not forward packets of this type. Storm control aims at preventing broadcast storms. A switch with storm control configured only controls incoming traffic on interfaces. If the average rate of unknown unicast packets received by an interface of a switch within the storm control interval is higher than the specified upper threshold, the switch blocks packets on the interface or shuts down the interface according to the configured penalty action. If the interface has been blocked, when the rate of packets received by the interface falls below the lower threshold, the switch unblocks the interface. If the interface has been shut down, you need to run the undo shutdown command to enable the interface. Take storm control on unknown unicast packets for example. Assume that the upper threshold for storm control on unknown unicast packets is 100 pps, the lower threshold is 20 pps, and the storm control detection interval is 5 seconds. If the interface receives more than 500 (100 x 5) packets within 5 seconds, the switch shuts down the interface. The interface can receive packets only after its status recovers to Up. Alternatively, the switch blocks all unknown unicast packets on the interface until the 5 seconds expire. When the number of packets received by the interface falls below 100 (20 x 5), the switch allows the interface to receive unknown unicast packets. For the incoming packets of the same type on an interface, only traffic suppression or storm control can be configured.

Traffic suppression module of S series switch
S series switches support the configuration of traffic suppression on the interface. Flow suppression contains three modes: Packet flow rate suppression Bit rate of flow suppression Percentage flow suppression Note: the cassette switch, only partial morphological support by bit rate traffic control.

Traffic suppression modes for S series switches
Traffic suppression can be configured on interfaces of S series switches. Traffic suppression has the following modes: By number of packets per second (pps) By number of bits per second (bit/s) By bandwidth percentage Note: Only some S series fixed switch models support traffic suppression by number of bits per second (bit/s).

Why is the actual suppression value different from the configured traffic suppression value
The traffic suppression supported by AR series routers is a type of granularity-based suppression. -The AR1200 series use the committed information rate (CIR) mode. If the traffic suppression value is between 64 kbit/s and 1000 kbit/s, the granularity is 64 kbit/s. For example, if the traffic suppression value is set to 65 kbit/s, the effective traffic suppression value is 64 kbit/s. If the traffic suppression value is set to 200 kbit/s, the effective traffic suppression value is 128 kbit/s, and so on. If the traffic suppression value is between 1000 kbit/s and 100,000 kbit/s, the granularity is 1000 kbit/s. For example, if the traffic suppression value is set to 1001 kbit/s, the effective traffic suppression value is 1000 kbit/s. If the traffic suppression value is set to 2999 kbit/s, the effective traffic suppression value is 2000 kbit/s, and so on. -The AR2200 , AR3200 and AR3600 series use the packet mode. The granularity is 125 packets per second (pps). If the traffic suppression value is set to 10 pps, the effective traffic suppression value is 0 pps. If the traffic suppression value is set to 126 pps, the effective traffic suppression value is 125 pps, and so on. Therefore, if the traffic suppression value is not set to a multiple of the granularity, the actual suppression value is different from the traffic suppression value that is set. Within a specified granularity range, all suppression values are correct.

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