Network Connection Problems - Omron CS Series Operation Manual

Troubleshooting Procedures
8-4-6

Network Connection Problems

Network connection problem occurred.
Go through the procedure in
Startup Problems before
starting this procedure.
Is the LNK indicator
lit?
Y
Execute the ping
command for all nodes
connected to the network.
Did all nodes
fail to respond to ping
command?
N
Did a particular
node fail to respond to
ping command?
N
Is the remote
node functioning as an
FTP client?
N
Execute FINS PROTOCOL
STATUS READ.
E N D
Is the twisted-pair
N
N
cable secured?
Y
Is the twisted-pair
N
cable between the Ethernet Unit
and the hub straight
cable?
Y
Only SD indicator
is flashing.
Y
Y
Y
• Firmly secure the cable.
• Use straight cable.
• Replace first the twisted-pair cable, then the hub,
and then the Ethernet Unit, in order.
• Power may not be being supplied to the hub.
• The twisted-pair cable for that node may be
disconnected.
• The remote node may not support ICMP.
• Connect by FTP.
• If the following parameters are counted, the corresponding
communications services may not be possible with the remote
node.
[IP status] (2) (3) (5) (6) (All communications services)
[ICMP status] (5) (6) (7) (8) (ping)
[TCP status] (3) reception status (4) (5) (6) (FTP, TCP sockets)
[UDP status] (1) (2) (3) (FINS communications, UDP socket)
• If the following parameters are counted, the load at the Ethernet
Unit may be too high. Adjust the user applications.
[IP status] (4) (8) (9)
Section 8-4
223