Adjusting MDI/MDIX auto-detection settings.

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We have found that with a few types of POE switches/routers that support Auto MDI/MDIX detection, as well as one brand of POE AC wall adapters, some of our cameras are not always properly detected. Because of this, occasionally the camera will not be recognized properly, and not get powered up. Apparently the auto detection functions in the camera get confused as the network switch tries to auto detect the wiring of the camera cable. This only occurs only with certain switches/routers. One way to test or solve this problem, if you are using a an Auto MDI/MDIX, POE, switch/router to power up the cameras, would be to turn off or disable the auto MDI/MDIX detection on either the switch/router, or on our camera. Sometimes it is as simple as pushing a button on the switch/router. Sometimes you have to go into the user interface on the switch/router. But, if you would prefer to try turning off the Auto MDI/MDIX function in the camera, you can follow these command line instructions:


1. Plug the cable from your router/switch/power supply into the camera, and give it 30-60 seconds to boot. (Do this several times if necessary to get the camera to boot, and the network connection lights to start flashing)

2. Login to the camera's file system by typing the following commands:

  ' telnet <camera ip> '  (example: telnet 192.168.0.9)
  Elphel353 login: root
  Password: pass

3. Edit one of the camera's network configuration files using the text editing program ' VI ':

  ' vi /etc/conf.d/net.eth0 '

4. Press the <Insert> key to enable the editing functions

5. Change the value of the variable AUTONEG from

  'AUTONEG=normal', to ' AUTONEG=never '

6. Just below the AUTONEG variable, insert the following variable:

  ' MDI_MODE=mdi '

7. Press <Escape> to exit editing mode, and type the following command to save and quit:

  ' :wq '

8. The last thing to do before attempting to reboot the camera, is to synch the changes to the permanent flash memory:

  ' sync '

Now try rebooting the camera several times, and it should boot up every time.