M A G N U M 6 K S W I T C H E S , M N S - 6 K U S E R G U I D E
F
IGURE
92
–
Normal RSTP/STP operations in a series of switches. Note – this normal status is
designated RING_CLOSED
BP
DU
Tra
ffic
Forwarding
Port
Blocking
Port
BP
DU
Tra
ffic
Forwarding
Port
Blocking
Port
This normal status is designated as RING_CLOSED. Operations will continue this way
indefinitely until a fault occurs.
A fault anywhere in the ring will interrupt the flow of standard RSTP/STP status-checking
BPDU packets, and will signal to RSTP/STP that a fault has occurred. According to the
standard RSTP/STP defined sequence, protocol packets are then sent out, gathered up and
analyzed to enable RSTP/STP to calculate how to re-configure the LAN to recover from the
fault. After the standard RSTP/STP reconfiguration time period (typically 20 to 30 seconds),
the RSTP/STP analysis concludes that recovery is achieved by changing the blocking port of
the ring port-pair to the forwarding state.
Intentionally left blank
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