Based on the onsite
environment, the main network environment is described as follows:
The H3C S10500 functions
as the core switch, and the Huawei S12708 functions as the aggregation switch.
The two devices are connected through 40GE ports, and the S12708 is connected
to two access switches (S5700s) and servers.
2. Related problems
(1) A large number of packets will be lost when
terminals at both ends ping each other.
(2) Two switches are directly connected. After the
ping command is run on the switch, packet loss still occurs.
(3) When the S5700s connected to the S12708 are
directly connected to the core switch S10500, and the ping operation is
performed on the terminal, no packet loss occurs.
(1) Check the physical connection of the device. It is
found that the packet loss is not caused by the loop. (2) Check the hardware status of the device. It is
found that the hardware status is normal and no exception occurs.
(3) Collect the diagnostic log information of the
device and check recent operations of the device. No violation occurs, and the
log information of the device is normal.
(4) Replace the optical module and optical fiber. The
media is normal.
(5) Change the cable between the S12708 and S10500 to
the cable of the 10GE card. Configure the cable to ensure that the link is
normal. Run the ping command. It is found that packet loss still occurs.
(6) Perform traffic statistics collection on uplink
and downlink interfaces of the S12708. The statistics are mainly about ICMP
packets. The result shows that only unidirectional data flows pass through the
(7) According to the log information, the aggregated
interfaces directly connected to the two switches receive a large number of
BPDUs. After communication with the R&D engineers, it is recommended that
you disable the spanning tree protocol and then run the ping command. The data
forwarding on the interfaces is normal. No packet loss occurs and the problem
spanning tree protocol is incompatible between different vendors.
physical loop exists on site. The spanning tree protocol of Huawei S12708
switch is disabled. No packet loss occurs and the problem is solved
disabled on Huawei S12708 based on onsite situation. The reason is that STP
convergence may be different when Huawei devices are interconnected with
third-party devices. When two vendors interconnect with each other, STP
convergence occurs. During STP convergence, the interface does not forward
traffic. Therefore, packet loss occurs. After the convergence is complete, the
fault is rectified. If convergence is performed periodically and BPDUs are
continuously sent, this problem will occur.