How do S series switches handle packets with all-0 MAC addresses

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You can configure an S series (except the 1700) and E series switch to discard or forward packets with all-0 source or destination MAC addresses.
The drop illegal-mac enable command enables a switch to discard packets with all-0 MAC addresses. By default, a switch does not discard packets with all-0 MAC addresses.
The drop illegal-mac alarm command configures a switch to generate an alarm when receiving packets with all-0 MAC addresses.
Note:
The drop illegal-mac alarm command allows a switch to generate only one alarm. To enable the switch to generate more than one alarm. reconfigure the drop illegal-mac alarm command.

Other related questions:
Do all interfaces have MAC addresses

Each Layer 3 Ethernet interface has a MAC address.

A VLANIF interface obtains the device MAC address as its own MAC address. This MAC address is fixed.

A Bridge-if interface obtains the device MAC address as its own MAC address. This MAC address can be changed using the CLI.

The MAC address of a Layer 2 interface has no function on the AR.

NOTE:
  • To change the device MAC address, run the set system-mac { current | default } command in the diagnosis view, save the configuration, and restart the device.

  • The system MAC address to be modified cannot be a multicast MAC address.


Handling of many ARP request or replay packets received on S series switches
When S series switches receive a large number of ARP Request or Reply messages, the following problems may occur: -Users get offline, are frequently disconnected, experience slow Internet access and service interruption, or even cannot access the network. -The switches have high CPU usage or cannot be managed by the network management system (NMS), and their connected devices go offline. -Ping delay, packet loss, or failure occurs. You can perform the following steps to troubleshoot the preceding problems: Saving the results of each step is recommended. If your troubleshooting fails to correct the fault, you can provide the record of your actions to Huawei technical support personnel. 1. Run the display cpu-defend statistics packet-type { arp-request | arp-reply } all command in the user view to check whether the count of the dropped ARP Request or ARP Reply packets is increasing. -If the count is 0, the switches do not drop any ARP Request or Reply packets. Then go to step 6. If the count is not 0, the rate of ARP Request or Reply packets exceeds the CPCAR rate limit and excess ARP packets are discarded. Then go to step 2. 2. Run the display cpu-usage command in the user view to check the CPU usage of the MPU. - If the CPU usage is in the normal range, go to step 3. - If the CPU usage is higher than 70%, go to step 5. 3. Run the car command in the attack defense policy view to properly increase the CPCAP rate limit for ARP Request or ARP Reply packets. Note: Improper CPCAR settings will affect services on your network. It is recommended that you contact Huawei engineers before adjusting the CPCAR settings. The car command takes effect after you apply the attack defense policy. If the fault persists or the fault is removed but the CPU usage is still high, go to step 4. 4. Capture packet headers on the user-side interface and find the attacker according to the source addresses of ARP Request or Reply packets. If a lot of ARP Request or Reply packets are sent from a source MAC or IP address, the switches consider the source address as an attack source. Run the arp speed-limit source-ip [ ] maximum command in the system view to reduce the ARP packet rate limit based on the source IP address or run the arp speed-limit source-mac [ ] maximum command to configure ARP packet rate limit based on the source MAC address to adapt to actual network situations. By default, the function of ARP packet rate limit based on the source IP address is enabled, and the switches allow a maximum of 30 ARP packets with the same source IP address to pass through every second. After the rate of ARP packets reaches this limit, the switches discard subsequent ARP packets. The rate limit for ARP packets with the same source MAC address is 0, that is, the switches do not limit the rate of ARP packets based on the source MAC address. After the ARP packet rate limit based on the source IP address or MAC address is set to a smaller value (such as 5 bit/s), --If the fault persists, go to step 5. -- If the fault is rectified but the CPU usage is still high, configure a blacklist or a blackhole MAC address entry to discard ARP packets sent by the attack source. After that, if the CPU usage is still high, go to step 6. 5. Capture packet headers on the user-side interface and find the attacker according to the source addresses of ARP Request or Reply packets. If a lot of ARP Request or Reply packets are sent from a source address, the switches consider the source address as an attack source. You can configure a blacklist or a blackhole MAC address entry to discard ARP packets sent by the attack source. If the fault persists, go to step 6. 6. Collect the following information and contact Huawei technical support personnel: Results of the preceding troubleshooting procedure Configuration files, logs, and alarms of the switches

Do S series switches support static multicast MAC addresses
S series switches (except the S1700) support static multicast MAC addresses in V100R006 and later versions. However, the support for this function varies depending on switch models. - S2700SI/S2700EI: not supported - S3700SI/S3700EI: not supported - S5710-C-LI: not supported - S5700SI: supported in V200R003 and later versions

Whether S series switches support IPSG
All S series switches except the following support IPSG: S1700 switches S2700-SI switches W series cards of S7700, S9700, and S1270 switches S9300 of earlier versions than V100R002 For switches that do not support IPSG, you can run the mac-address static vlan command to configure static MAC addresses and run the mac-address learning disable command to disable MAC address learning on interfaces to realize a function similar to IPSG.

Specification of the MAC address table on an S series switch
Hi, I cannot answer this question. For details about product specifications, click http://e.huawei.com/en/service-hotline to look up the contact method of your local customer service engineers.

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