Expand Configuration and Management Manual (G06.24+)

Troubleshooting
Expand Configuration and Management Manual—523347-008
21-37
Node Not Available
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NEXTSYS modifier value. A large number of Level-2 DISC (disconnect)
supervisory frames usually indicates an incorrect NEXTSYS number.
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Interface selection (RS-232 or RS-422). The controller defines its pinouts by the
proper setting of the interface.
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ASSOCIATEDEV modifier and the system load command files for Expand-over-
X.25, Expand-over-SNA, and Expand-over-IP, Expand-over-ATM, and Expand-
over-FOX line-handler processes.
If all the lines in the path are down, look for a common problem such as a processor
failure, a SWAN concentrator or Ethernet adapter down, lack of power to a bank of
modems, or even a problem with the communications facilities.
If the line or lines are operational but the path is down, the problem is probably with the
path procedures, or Layer 4 portion, of the Expand line-handler process.
Line(s) Down
If you identify that the problem is caused by a downed (nonoperational) line, take the
following steps:
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Unless you suspect a common problem, verify that the line is down by checking
each individual instance of a line failure.
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Use SCF to verify that the line is in the STOPPED or STARTING states (unable to
go to the START state).
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If the problem is multiple lines down and is caused by a SWAN concentrator or
Ethernet adapter, document the problem and call your HP representative.
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Use SCF to obtain Layer 2 statistics and look for the following:
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A high number of SABM and DISC frames, indicating that the link was
repeatedly attempting to come online.
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A high number of SABMs sent, indicating that the other side of the line may
have problems.
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Driver problems. A high number of BCC (FCS) errors, error frames, and/or line
quality below 100 percent could indicate a noisy line, defective modem, or bad
controller port.