Troubleshooting Fiber Distributed Data Interface - Internetworking Troubleshooting - page 109

Table5-2 show interfaces fddi Field Descriptions (continued)

Field Description

neighbor State of the neighbor:

A —Indicates that the CMT 1 process has established a
connection with its neighbor. The bits received during the
CMT signaling process indicate that the neighbor is a
Physical A type DAS 2 or concentrator that attaches to the
primary ring IN and the secondary ring OUT when
attaching to the dual ring.
S —Indicates that the CMT process has established a
connection with its neighbor and that the bits received
during the CMT signaling process indicate that the
neighbor is one Physical type in a single-attachment
station SAS. 3
B —Indicates that the CMT process has established a
connection with its neighbor and that the bits received
during the CMT signaling process indicate that the
neighbor is a Physical B dual attachment station or
concentrator that attaches to the secondary ring IN and the
primary ring OUT when attaching to the dual ring.
M —Indicates that the CMT process has established a
connection with its neighbor and that the bits received
during the CMT signaling process indicate that the
router's neighbor is a Physical M-type concentrator
serving as a master to a connected station or concentrator.
unk —Indicates that the network server has not completed
the CMT process and, as a result, does not know about its
neighbor.

cmt signal bits Shows the transmitted/received CMT bits. The

transmitted bits are 0x008 for a Physical A type and
0x20C for Physical B type. The number after the slash ( / )
is the received signal bits. If the connection is not active,
the received bits are zero ( 0 ); see the line beginning
Phy-B in the display. This applies to FDDI processor FIP 4
interfaces only.

status Status value displayed is the actual status on the fiber. The

FDDI standard defines the following values:

LSU —Line state unknown, the criteria for entering
or remaining in any other line state have not been
met.

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NLS —Noise line state, entered upon the occurrence
of 16 potential noise events without satisfying the
criteria for entry into another line state.

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MLS —Master line state, entered upon the receipt of
eight or nine consecutive HQ or QH symbol pairs.

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