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UTMC OTU/MOVA Handbook
667/HB/31601/000
Page 111
Issue 5
8.3 COMMUNICATIONS FAILURES
Symptom
Possible Diagnosis
Action to Check Diagnosis
(a) Unit will not
communicate with the
Instation
Incorrect IP address
Use the ‘WIZ’ command to display the
IP address, Netmask and Gateway
settings and check these are as recommended by the Network Administrator.
An incorrect
Gateway
value can keep the Ethernet from being brought up. Use
the ‘network’ command to check if the Ethernet is up.
Duplicate IP address
Disconnect the outstation from the network and then use the ping command
from the instation to ping the allocated outstation address. If there is a
response to the ping command then the IP address already exists on the
network and the conflict of addresses will need to be resolved.
Network Connectivity
Fault
Use the ping command (see reference 1.3.1) to check if the outstation can
transmit to a known IP address on the network e.g. the Gateway address.
From the instation, use the ping command to check IP connectivity to the
outstation IP address.
If the ping command works, then the Ethernet, modem & Network are
connected – proceed to the next Possible Diagnosis.
If the ping command fails, then check/replace each component in turn,
including the interconnecting cables. The outstation Ethernet can be tested by
plugging into a hub/PC off the network. Some modems have a separate IP
address which can be tested with ping to check IP connectivity.
NB: The route command (see reference 1.3.1) can be used to check if the
outstation is receiving any packets at all on the Ethernet.