Cabletron Systems SPECTRUM TRMMIM, User Manual

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Alarm Configuration
4-8 Setting and Viewing Station Alarms
AC Errors Also known as ARI/FCI errors, AC errors occur during
the Ring Poll or Neighbor Notification process when one
station fails to correctly set the ARI (address recognized)
and FCI (frame copied) indicator bits on the current AMP
(active monitor present) or SMP (standby monitor
present) frame intended for it, thus leaving its
downstream neighbor without an accurate upstream
neighbor’s address. AC errors are detected when a
station receives more than one AMP frame with ARI and
FCI bits still set to 0 without seeing an intervening SMP
frame with its bits set to 1, or when the station detects an
SMP frame with its ARI and FCI bits set to 0 without
having seen an AMP frame with its ARI and FCI bits set
to 1. When a station detects an AC error, it stops the Ring
Poll process by not issuing its own SMP frame; no other
ring recovery procedures are initiated.
Congestion A congestion condition occurs when a station recognizes
Errors a frame addressed to it, but is unable to copy the frame
because it has no available buffer space. Although this
may indicate a station which is performing poorly, no
ring recovery procedures are initiated. Note that the
count of congestion conditions reflects the number of
times
frames have been dropped, not the number of
frames dropped.
The Station List box lists the stations detected on the selected ring, the module
and port through which they are connected, the name of the station (if one has
been assigned), and the status and threshold of the alarm type highlighted in the
alarm list.
The Threshold field allows you to configure a new threshold for the selected
alarm type; the new threshold will be applied as indicated by the current selection
in the Set Alarm For field.
NOTE
A station listed at module and port 0 is part of the TRMMIM-managed ring, but not
directly connected to the TRMMIM-controlled hub (or TRMMIM). You can still set
alarms for these stations.
NOTE
When setting thresholds for station-level alarms, keep in mind that the TRMMIM is
counting occurrences of the selected variable on individual stations only, not all
occurrences on the ring. Note, too, that station-level alarms can only be set for isolating
errors — that is, those that do pinpoint a specific trouble spot on the ring. Station alarm
notification (traps) will include the address of the offending station.