Hello.

I have a crazy random issue that pops up from time to time and I can't reproduce it for the life of me. I have a printer that is connected to my network via cat5 that will once in a while print the first page of a document just fine but all pages after that will come out in jibberish.

This issue has happened with several printers, so I know it's not the printer, and has happened with several computers with different operating systems (windows xp, 7, 8, ubuntu, various other *nix). The only thing I can think of next is the cat5 cable connected to the printer. Printing to this printer and others via usb works perfectly, every time.

The thing is that I can't just replace the cable as it's run through a wall and ceiling. So I was thinking, maybe I could catch it in the act via some sort of network program that can see what is going on.

Is there any such software that I can use to monitor/check/test this out? The issue doesn't happen all the time, but hopefully I can catch it when it does.

Thanks for any help, and if you have any more ideas for me on how to solve this, please help.

I would suspect random noise getting injected into the cable. CAT5 is pretty robust, but if you have a longish run of it and it is running parallel to, and in close proximity to, something like household 120v wiring (as may be the case if it was run inside walls) you could have a problem there. Or, if the cable was nicked by a nail or screw or something within the wall that compromised it's integrity you could see problems there as well.

You said the problem is random. How frequent is it? If you print a set of pages and some come out bad, can you reprint that exact same document and have it come out good the next time? Can you move the printer close to your router/hub/switch and plug it in using a seperate short CAT5 cable and run some tests? That might be tough, depending on how frequent your random problem is. Intermittant stuff can be a devil to debug.

Ok, the run is only about a 40 foot cable, maybe 50 feet. When the issue happens, it can be quickly reproduced for a few minutes by just doing a reprint. But, if you wait about an hour, it will print fine.

What is crazy is that the house it's in has horrible wifi. We had to run this cable a while back because the wifi signal in the house would not go more than 20 feet. I have no idea what is killing it and have tried multiple devices. Anyway, I am guessing that whatever is killing the wifi signal is also affecting the cat5 cable somehow, but I don't know how. It's not like there are lead in the walls. It's a regular house. It does have solar panels though, but no battery backup system for them.

I will try to test the printer with another cable and move it closer to the router, but the problem is that it's hard to tell if it's just not acting up at that time vs if it is a solution that will work.

Thanks

Any software I can test? I was thinking it'd be great to stick a linux computer on each end of the cable and somehow check if something is happening to the packets as I transfer data between them, or one linux computer and the printer and check that.

If you have a spare box you could add an extra eth to you could put it in front of the printer, make it transparently forward traffic between devices and tcpdump there and on the client side? Else how about connecting the printer to a Linux box, make it a print server and if necessary sniff there? Just thinking out loud...

"Electrical power." Put a UPS box on all the equipment, and (in addition ...) check what is actually attached to each electrical circuit.

Good point by sundialsvcs. As I think more about this, I would tend to agree that dirty electrical power is the more likely culpret. Could still be noise/interference in the wiring, but dirty power is more likely. I'm glad sundialsvcs thought of this. Definitely worth investigating.

Also, since you say it is failing for a period, but then starts working later, what is going on in your house at the time it is failing? Your wife didn't just fire up her high powered radio transmitter next to the printer did she? Obviously I'm joking about that, but do look around for things that might be generating electrical noise. Cheap appliances are sometimes known for this - hair driers, blenders, fans, etc. Some power tools. You don't happen to have any of those old X10 "Home automation" light switches that work by remote control in place do you? Those place high frequency signals on your power lines. I haven't found those to cause problems with other devices myself, more so other devices cause problems for them, but it's still something to consider.

Sounds good, I will check all these things out.

Thanks

Hello,
Did you resolve your problem??