How can an S series switch ping another device using ping packets carrying a specified source IP address

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For S series switches (except the S1700), you can specify the source IP address of ping packets by specifying the -a source-ip-address parameter in the ping command.
For example, set the source and destination IP addresses of ping packets to 192.168.150.107 and 10.135.19.157, respectively.
[HUAWEI] ping -a 192.168.150.107 10.135.19.157

Other related questions:
An S series switch fails to ping the remote device using ping packets carrying the source IP address. Why the ping succeeds after the source IP address is changed
For S series switches (except the S1700), the possible reason why the ping succeeds after the source IP address is changed is that the remote device does not have a return route to send response packets. If the ping succeeds after you change the source IP address or do not specify any source IP address in the ping command, you need to check whether the remote device has a return route.

How is the source IP address of ping packets specified
The -a parameter specifies the source IP address of ping packets. If -a is not specified, the system searches for the outbound interface mapping the destination IP address in the routing table and uses the outbound interface's IP address as the source IP address of ping packets. If there are equal-cost routes to the destination IP address, the system performs the hash algorithm based on the destination IP address, protocol number, ICMP type, and ICMP mode and selects the outbound interface's IP address as the source IP address of ping packets.

Question about packet loss when the rate of ping packets is high on S series switches
When another device pings an S series switch (a non-S1700 switch), the device and the switch exchange ICMP packets. To protect the CPU, you can run the icmp rate-limit command to configure a rate threshold for ICMP packets. The undo icmp rate-limit command restores the default rate threshold of ICMP packets.

How can a PC connected to an S series switch ping the IP address of the remote device using the HyperTerminal
A PC connected to an S series switch can directly ping the IP address of the remote device using the HyperTerminal.

The reason of S series switch Ping packet loss
For S-series chassis switches: The Ping packets of the local switch are processed by the switch as a fib-hit packet. For packets of type fib-hit, the switch sends to CPUs at the default CAR value to prevent this type of packets from impacting the CPU. In the case of the default CAR value, the number of ping packets per second is too large for the CAR value, so the switch will discard some packets. Increase the fib value of fib-hit, you can solve the packet loss problem.

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