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Product FAQs


When I install the NPort Real-TTY driver on Debian Linux, I see the following error message in the npreald.log file: Master tty open fail (/proc/npreal/0)! How do I rectify this issue?


To rectify the NPort Real-TTY driver on Debian Linux host, do the following:

  1. Confirm that there is an ldnpreal script file, with the following content, under the /usr/lib/npreal/driver/ path on your Debian Linux host computer.

    If the script file does not exist, create a script file called ldnpreal and save the following content into the file:

  2. Run the following command to set read, write, and execute permissions for the script:

    # chmod +x ldnpreal
  3. Copy the ldnpreal script file into the path: /etc/init.d and then run the following command:

    # update-rc.d ldnpreal defaults 90
  4. Reboot your Debain Linux host.

When your host system starts up, it will automatically load the ldnpreal script and the TTY driver issue should be solved.

Relevant Products

CN2600 Series · EDS-205A Series · MiiNePort E1 Series · MiiNePort E2 Series · MiiNePort E3 Series · MiiNePort W1 Series · NE-4100 Series · NE-4100-ST Series · NPort 5000AI-M12 Series · NPort 5100 Series · NPort 5100A Series · NPort 5200 Series · NPort 5200A Series · NPort 5400 Series · NPort 5600 Series · NPort 5600-DT Series · NPort 5600-DTL Series · NPort 6100/6200 Series · NPort 6400/6600 Series · NPort Express Series · NPort IA5000 Series · NPort IA5000A Series · NPort IA5000A-I/O Series · NPort IAW5000A-I/O Series · NPort P5150A Series · NPort S8000 Series · NPort W2150A/W2250A Series ·

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