Proactive loop detection detects and eliminates Layer 2 network loops. When a device's Ethernet or Eth-Trunk interface physically goes Up or an interface is bound to a VSI, the device proactively detects and eliminates loops, if any.
If a device's Ethernet or Eth-Trunk interface goes Up by misoperation or an interface is bound to a VSI and the interface incurs a loop, the device may have services interrupted or even get out of the NMS control. To resolve the loop problem and ensure normal device running, Huawei developed proactive loop detection upon interface Up. This feature allows a device's interface to proactively send loop detection packets. If the interface detects a loop, the device blocks the interface.