You can take a bridge port extender (BPE) offline if needed. Note that disabling a cascade port takes the directly attached BPE offline with any downstream attached BPEs. When a BPE is taken offline, its extended ports go into a link down state.
To take a BPE offline, use the following command specifying the cascade port that the BPE is attached to in port_list (do not use the all option):
disable port [port_list | all]