Description Of The Traffic-Suppress Command - Huawei MA5600 Manual

NGN Cases
1.2

Description of the Traffic-suppress Command

Title: Description of the Traffic-suppress Command
ID: SE0000352530
Information
Troubleshooting Cases
Type :
Product Family: Broadband Access
Fault Type: QACL Service
Keywords: traffic-suppress
Permission Level: Warranty Users Permission
Phenomenon Descr
The traffic suppression is used to suppress the traffic of the broadcast, unknown unicast, and
iption:
unknown multicast packets in the inbound direction of the port. For the broadcast and unknown
unicast, the suppression is implemented according to the number of the packets. For the
unknown multicast, the suppression is implemented according to the traffic of the packets. This
command is mainly used to avoid the effect on the system and the network after a large number
of such packets are broadcasted.
The broadcast packets refer to the packets whose destination MAC addresses are all Fs, such as
ARP packets, PADI packets in PPPoE protocol, and DHCP discover packets in DHCP protocol.
Many protocols send the handshake packets through broadcast.
The unknown unicast packets refer to the packets whose destination MAC addresses are unicast
MAC addresses. In the LAN switch chip of the control board, however, no forwarding entry
related to the destination MAC addresses is created, so the LAN switch chip does not know to
which port the packet is forwarded. In this case, the MA5600 broadcasts the packets in the
VLAN where the port that sends the packets is located. If too many unknown unicast packets
(for example, caused by the malicious attack) are broadcasted, the congestion occurs or even the
ongoing service is interrupted. Therefore, the traffic suppress command is used to suppress the
unknown unicast packets.
The unknown multicast packets refer to the packets whose destination MAC addresses are
multicast MAC addresses (the highest bit of such MAC address is 01, such as the MAC address
of IGMP packets and some BPDU packets). In the LAN switch chip of the control board,
however, no forwarding entry related to the destination address is created, so the LAN switch
does not know to which port the packets are forwarded.
Alarm Informatio
Null
n:
Cause Analysis:
Entry Description:
MA5600(config-if-scu-0/7)#display
{ board<K>|port<K>|mirror<K>|traffic-suppress<K> }:traffic-suppress
{ portid<U><0,7>|all<K> }:all
Commands:
display traffic-suppress all
Traffic suppression ID definition:
---------------------------------------------------------------------
NO. Min bandwidth(kbps) Max bandwidth(kbps) Package number(pps)
---------------------------------------------------------------------
1 6 145 12
2 12 291 24
3 24 582 48
4 48 1153 95
5 97 2319 191
6 195 4639 382
7 390 9265 763
8 781 18531 1526
9 1562 37063 3052
10 3125 74126 6104
11 6249 148241 12207
12 12499 296483 24414
---------------------------------------------------------------------
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Chapter 1 MA5600 Cases
Quality Level:
B
Product: SmartAX MA5600