FL NAT SMN 8TX(-M)
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RSTP fast ring detection
The “RSTP Fast Ring Detection” function can be activated on the “RSTP Configuration” web
This function speeds up the switch-over to a redundant path in the event of an error and
provides easy diagnostics. RSTP fast ring detection provides each ring with an ID, this ID is
made known to each switch in the relevant ring. A switch can belong to several different
rings at the same time.
Structure of the ring ID
The ring ID consists of the port number of the blocking port and the MAC address of the
corresponding switch. Advantages of the ring ID:
–
Easier to identify redundant paths and locate blocking ports.
–
Possible to check whether the desired topology corresponds to the actual topology.
Figure 5-7
RSTP ring table
Information in WBM
The following information is displayed on the web page (and via SNMP):
Local ring ports
These two ports of this switch belong to the ring that is listed (ring ID).
Blocking port
This port deliberately breaks the loop.
Ring detection states
The following states can occur for ring detection:
–
Not Ready
- Ring detection has not yet been completed.
–
OK
- Ring detection has been completed and quick switch-over is possible in the event
of an error.
–
Broken
- The ring is broken on this branch in the direction of the root switch.
–
Failed on Port A - The ring was broken on this switch at port A.
Ring ID
A blocking port does not receive LLDP BPDUs, but does send LLDP BPDUs.
In the event of a link failure in the ring, the “trapRstpRingFailure” trap is sent.
If “Broken” or “Failed” status lasts for longer than 60 seconds, it is no longer displayed
after the next topology modification, since these rings no longer exist.
