Figure 12 New Root Bridge - Zte ZXR10 5900 Series User Manual

ZXR10 5900/5200 Series User Manual (Ethernet Switching Volume)
F 12 NEW ROOT BRIDGE
IGURE
In Figure 12, switch D takes part in calculating spanning tree. If
priority of switch D is lower than that of switch A. Switch D is
elected to be a new root switch. After calculating spanning tree,
port of switch B which connects to switch A is blocked.
Port root protection command is configured in interface mode. It
is only permitted in designated port and is not permitted in root
port. A port which enables root protection receives BPDU packets
from a neighbor switch and knows the neighbor switch has smaller
priority. Port will enter ROOT_INCONSISTENT state.
In Figure 12, port of switch C that is connected to switch D should
be configured as protection. Once this port receives a BPDU packet
which contains smaller priority than root switch, this port will en-
ter ROOT_INCONSISTENT state and stops transmitting any data
packet. Once switch D stops sending the BPDU packet which con-
tains smaller priority. Port of switch C will resume transmitting
data packets automatically.
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