Customer noticed that on NE05’s are regularly broadcasting packets that are completely unknown with ethertype 0x999a, which is an unregistered ethertype.
What is this, and how can be disable it?
Solution
He receive those packets because you have configured loopback-detect command on device.
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loop-detect trigger enable
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After the loopback-detect command is run, the device sends special detection packets whose Ethernet type is 0x999a. In the packets, the destination MAC address is the broadcast address and the source MAC address is the device's MAC address. If a port receives detection packets from itself, there may be a loopback fault and the port blocks itself while reporting an alarm. If the port does not receive the detection packets after the delay time elapses, the loopback fault has been rectified and the port automatically cancels the block.