Context
If a device does not receive any BPDUs from the upstream device within the timeout interval, the device considers the upstream device to have failed and recalculates the spanning tree.

Sometimes, a device cannot receive the BPDU from the upstream device within the timeout interval because the upstream device is busy. In this case, recalculating the spanning tree will cause a waste of network resources. To avoid wasting network resources, set a long timeout interval on a stable network.

If a switching device does not receive any BPDUs from the upstream device within the timeout interval, spanning tree recalculation is performed. The timeout interval is calculated as follows:

Timeout interval = Hello time x 3 x Timer Factor

Procedure
Run:
system-view
The system view is displayed.

Run:
stp timer-factor factor
The Timer Factor value is set. This parameter determines the timeout interval during which the device waits for BPDUs from the upstream device.

By default, the timeout period is 9 times the Hello timer value.