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The full path to the log file is /ippe/logs/ippe.log and the most flexible way to access it is to ssh (or putty) to the IP address of the NE-ONE (standard ssh port 22).
The username is itrinegy and the password is itrinegy (to start with). You'll be logged in to the console and sitting in the console menu. One of the choices on this menu is to change the itrinegy username and password which you should do if the NE-ONE can be accessed outside of a lab (say).
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