D-Link Forums
The Graveyard - Products No Longer Supported => IP Cameras => DCS-930L => Topic started by: acellier on June 27, 2012, 04:52:13 PM
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My two separate IP cameras (a 930 and a 932) use ftp to store jpgs at my web site based upon motion detection. I use a php script to review images from a chosen day and half-hour interval.
Typically a jpg is about 45 kB; anywhere from none to about 300 may be stored in each half-hour folder, within a given day's folders. These half-hour interval parameters are set in the cameras.
Today on several occasions (maybe yesterday also) the site has stored several 0 byte ".jpg" files, from BOTH cameras, which brings my php script to a halt.
Also today, both cameras (at about the same time) deposited a timestamped folder INSIDE a timestamped folder where the jpgs normally go, which is not the proper behavior.
What would you guess - something weird going on with the servers, or my router, or simultaneously in the 2 cameras ?
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Occasional zero-byte, and partial, file transfers continue on the 930 (932 is out of service after bad firmware update).
I've modified my php image viewing script to convert the zero-byte jpgs to txt, so the script won't hang.
Also have experienced (rarer) yeardate folder sent *into* a yeardate folder, where only (halfhour) time folders should go, and very occasional incomplete photos - top of image only, terminated after substantial progress.
Had Cox Cable come out, they applied their universal solution - replaced connectors, added an attenuator pad in the line.
It seems to still be happening.
Seems that these cameras don't tend to do an ack handshake ? Certainly they don't sense a failed upload and try again.
Any ftp-knowledgable folks out there that can cast a light ?
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Over the past 7 days we have had about 75 + zero-size jpg files and 4 or 5 partial pictures.
The DCS-930L is only set to "5" fps, jpeq quality "very high", "Java". And the iPodTouch app only does a single camera at a time, whereas I had seen errors on both the 930 and 932 ...
I have a thought - in recent days I have been leaving an old iPodTouch running on MyDlink app, as a monitor of our driveway ... perhaps MyDlink prempts the ftp sequence ...
We are going to turn off any and all MyDlink monitors, and see if the zero-byte files stop ...
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They did not stop - got another 21 in a 3-hour period while we were off doing non-computer things.
Very puzzling.
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A new hypothesis - the "Smart Meter" installed by SCE in November - apparently may transmit at 2400 MHz (WiFi band) - SCE perhaps testing their "Wireless in-home networking" capabilities?
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No, not the smart meter - we moved the 930 to the other side of the house, still happens. Put it on Ethernet, wireless disabled - still happens. Very frustrating.
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more followup - we set the 930 to ftp into the router's USB memory, on a public port - so signal doesn't go thru internet - no errors, either wired or wireless.
Over the past 3 weeks, we've gotten several hundred zero-byte files; the coup de grace was the server locking me out for a faulty login by the camera, in the middle of the night.
We are concluding that Cox Cable is the culprit, as we have recorded cable modem downstream signal-to-noise ratio falling downward at unpredictable times, coupled with run-up of error counts. Techs out twice, new connectors and filter but the issue remains - even our typical signal is a bit below DOCSIS standards. Naturally, there is no available competitor for high speed internet.
I think the cameras share fault in not being robust ftp sources; tests from the computer using Fetch have all been clean.
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follow-up - almost certainly Cox Cable - since replacement of the video bandstop filter 2 weeks back, there have been no zero-byte files at all. This despite often marginal signal-to-noise ratios.