Cabletron Systems MICROMMAC-22T, User Manual

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INTRODUCTION
1-4
1.2.4 Monitoring And Diagnostic Indicators
Cabletron Systems front-panel LANVIEW LED (Light Emitting Diode)
system conveys information about the operational status of the
MicroMMAC-T and the network. See
Section 5.1 for information about
using LEDs to monitor MicroMMAC-T functions and conditions on the
network.
The MicroMMAC-T’s front-panel system message LCD provides system
information such as power-up diagnostics, Flash image revision levels, IP
addresses, and error alerts. See
Section 5.2 for complete information
about using the LCD system.
1.2.5 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 a 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
MicroMMAC-T learns the identity of the offending station and transmits
a Remove MAC frame to it to remove it from the ring.
The MicroMMAC-T transmits a trap 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 (MicroMMAC-T or STH) to which the offending station was
connected.
NOTE
The MicroMMAC-T automatically transmits BootP requests for
an operating image if the image in Flash is invalid or damaged.