FDDI Applications

The FDDI ConÞguration window displays the following Þelds:

MAC State

This Þeld indicates the current state of the MAC on the FDDI ring associated with the selected SMT entity. The RMT component of SMT monitors MAC operation and takes actions necessary to aid in achieving an operational ring. RMT occurs on a per-MAC basis and aids in the detection and resolution of failures, such as stuck beaconing and the presence of duplicate addresses.

¥Not AvailableÑthere is no MAC on the FDDI ring associated with this SMT entity, or the selected SMT entity is not attached to the main ring through the backplane FNB A and B ports.

¥Ring-OpÑthe ring is functioning normally. While in this state, the MAC being managed is part of an operational FDDI ring.

¥IsolatedÑthe SMT has just initialized RMT or RMT has entered this state during a path test (trace) after ring beaconing; RMT is not aware of the ring path or state.

¥Non-OpÑthe MAC being managed by the selected SMT is participating in ring recovery; the ring is not operational.

¥DetectÑthe claim (beacon) process of the FDDI ring protocol has exceeded one second. In this state, the ring is still alive, but no data is being transmitted. This may indicate a problem on the ring, including the detection of duplicate address conditions.

¥Non-Op-DupÑthe ring is not operational; the address of the MAC under the control of the SMT entity is a duplicate of another MAC on the ring. The duplicate address condition prevented ring recovery and initialization after a claim and beacon process. This state will not occur unless you are using locally-administered addresses, as factory-set MAC addresses are unique.

¥Ring-Op-DupÑthe ring is operational; however, the address of the MAC under control of the SMT entity has been found to be a duplicate of another MAC on the ring. Corrective actions will be attempted before the duplicate address condition causes ring initialization to fail after the claim and beacon recovery process. Like Non-Op-Dup, this state will not occur unless you are using locally-administered addresses.

¥DirectedÑthe beacon process did not complete within 7 seconds. The selected SMT has directed the controlled MAC to send beacon frames to notify the other stations that a serious problem exists on the ring, and a Trace state is soon to follow.

¥TraceÑa problem exists on the ring which could not be corrected during the beaconing process, and a Trace has been initiated. During a Trace (or Path Test), the SMT sends a signal that forces its nearest upstream neighbor to remove from the ring and conduct a self-test. If the ring does not recover, each subsequent upstream station will be forced to remove from the ring and conduct self-tests until the problem has been corrected. While the test is being conducted, ring management re-enters the isolated state.

The Configuration Window

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Cabletron Systems 2.2 manual MAC State