Licensing Requirements and Limitations for LBDT

Other network elements are not required.

LBDT is a basic feature of a switch and is not under license control.

All models of S2720, S5700, and S6700 series switches support LBDT.

For details about software mappings, visit Hardware Query Tool and search for the desired product model.

In V200R008C00 and earlier versions, LBDT does not take effect in dynamic VLANs. In V200R008C00 and later versions, the LBDT-enabled switch can detect loops in dynamic VLANs, but the Quitvlan action is invalid for dynamic VLANs.
LBDT requires that the device should send a large number of detection packets to detect loops, occupying system resources. Therefore, disable LBDT if loops do not need to be detected.
In versions earlier than V200R019C00, LBDT cannot be configured on an Eth-Trunk or its member interfaces. In V200R019C00 and later versions, LBDT can be configured on an Eth-Trunk but cannot be configured on its member interfaces.
On the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731-S, S5731S-H, S5731S-S, S5732-H, S6720-EI, S6720S-EI, S6720-HI, S6730-H, S6730S-H, S6730-S, and S6730S-S, manual LBDT can be configured on a maximum of 64 Eth-Trunks; on other models, manual LBDT can be configured on a maximum of 32 Eth-Trunks.
The blocked ports of LBDT cannot block GVRP packets. To ensure that GVRP runs normally and prevent GVRP loops, do not enable GVRP on the blocked port of LBDT.
The S2700-SI and S2710-SI support only detection of self-loops on an interface, and do not support detection loops on the downstream device or between interfaces.