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Old January 11th, 2017, 11:37 AM   #1

xinjiang is offline
Join Date: Mar 2010
Location: Calgary
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1756 cnbr controlnet net err

We have been using controlnet for a while. but suddenly two stations showed problems. both controlnet card showing NET ERR. Rsnetworx sometimes can find them but lose them quickly. I checked cable and connector. it seems good. Any suggestion? firmware is 5.37. Thanks.
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Old January 11th, 2017, 12:43 PM   #2
Ken Roach
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Location: Seattle, WA
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NET ERR means that there's a signal problem. Are you using single or redundant trunk cables ?

A visual inspection of the cable and connector is insufficient; replacing the tap is a good diagnostic step, but a ControlNet signal checker is really the only way to tell for sure the quality of the signal at a particular point in the network.
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Old January 11th, 2017, 12:46 PM   #3

nhatsen is offline
Join Date: Oct 2010
Location: Venezuela
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a) Read the ControlNet Coax Media Planning and Installation Guide and check again the cables and connectors.

b) How many nodes do you have in the network? A node number outside the Max Unscheduled Address can throw a NET ERR.

c) This kind of fault appears also if a module has a bad channel.

d) Read this note. There'are many known bugs in old ControlNet firmware.
"If you can't solve a problem, then there is an easier problem you can solve: find it." (George Pólya)
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