Difference between functions of the tracert command on a switch and a PC

The tracert command is used to discover the gateways that packets pass through from the source host to the destination host, check network connectivity, and locate network faults.
The execution process of the tracert command is as follows:
1. The source host sends a packet with the TTL being 1. After the TTL times out, the first hop sends an ICMP Error message to the source host, indicating that the packet cannot be forwarded.
2. The source host sends a packet with the TTL being 2. After the TTL times out, the second hop sends an ICMP Error message to the source host, indicating that the packet cannot be forwarded.
3. The source host sends a packet with the TTL being 3. After the TTL times out, the third hop sends an ICMP Error message to the source host, indicating that the packet cannot be forwarded.
4. The source host repeats the preceding process until the packet reaches the destination host.
When the tracert command is run on an S series switch (a non-S1700 switch), the switch sends UDP packets. The UDP port number of the three UDP packets starts from 33434 and is incremented by 1 every time the packets pass a hop. When one node on the packet forwarding path has equal-cost routes, the device forwards packets using a flow-based hash algorithm. The packets then are distributed to different links based on the calculation result. A maximum of three IP addresses on the equal-cost routes can be displayed each time.
When the tracert command is run on a PC, the PC sends ICMP packets, which are irrelevant to port number. If a network device on the packet forwarding path has equal-cost routes, the network device performs a flow-based hash operation and the ICMP packets are distributed to only one link, and the IP address of the link is displayed. However, if the network device performs per-packet load balancing, the ICMP packets are distributed to different links on the equal-cost routes.

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