Over a 2 to 3 week period, one would go offline, sometimes two. Four of eight M1054 cameras would go offline, same symptoms as you describe. I ran into this issue last year with a set of Axis M1054 cameras. The most recent episode happened yesterday (after a week of having no issues) and in the past 24 hours it has happened twice. The camera cable lengths vary between 50 to 250 feet but cameras on short cable runs will go down as well. I also connected one of the cameras to an Axis midspan POE injector but even that camera at one point went down as well. I have spoken with Digital Watchdog technical support people on several occasions and most recently they suggested to me that it may be a power issue so I replaced the switches. The only way that I can put the camera back on line is to power cycle it by shutting down the POE switch or unplugging the camera's ethernet cable. The camera that falls off line can be pinged but the you can not access the camera's web browser. It is not always the same camera and it is not always a camera on the same switch. Periodically (every three to seven days) one of the cameras falls off line. All of the cameras have been assigned static IP addresses that I was given by the IT people that manage their network. The system is installed in a small commercial environment and is connected to their network for internet access and local viewing. I'm using outdoor CAT5E cable to all of the cameras with the exception of two which have standard CAT5E. I am using two Trendnet eight port gigabit POE switches. The system consists of a Digital Watchdog NVR (Blackjack Blade - Spectrum) with eight Digital Watchdog DWC-MV421D 2.1 MP outdoor cameras. I am having an ongoing technical issue with an installation that I did a few months back.

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