Cabletron Systems TRMM-2, User Manual

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INTRODUCTION
1-3
1.1.2 Ring Poll Failure Recovery
The Cabletron Systems Ring Poll Failure Recovery Process automatically
removes any station that fails to correctly participate in the ring poll
process. This feature ensures that other stations are not prevented from
inserting into the ring by an unresolved ring poll failure condition caused
by a malfunctioning station on the ring. Upon detecting the presence of
Neighbor Notification Incomplete (NNI) frames on the ring, the TRMM-2
learns the identity of the offending station and transmits a Remove MAC
frame to the station to remove it from the ring.
The TRMM-2 transmits a trap (if traps are enabled) to the Network
Management Station (NMS) notifying the NMS that it was either able or
not able to correct the ring poll failure condition. If the recovery process
corrects the ring poll failure condition, the trap notifies the NMS that the
condition was corrected and specifies the offending station’s MAC
address and the port on the hub to which the offending station was
connected.
If the offending station cannot be definitively removed from the ring by
the recovery process (that is, if the offending station repeatedly attempts
to re-insert before the recovery process has concluded), a trap notifies the
NMS that the condition was not corrected and also identifies the last
station to correctly participate in the ring poll process. This information
helps network-management personnel to pinpoint the offending station,
which may need to be physically disconnected from the lobe port to
resolve the problem.
1.1.3 Network Management
The TRMM-2 allows you to monitor, configure, and manage networks
using:
• Out-of-band Local Management (LM) application
•
A variety of in-band SNMP network management software, including
the Cabletron Systems SPECTRUM family.