ian072@sundown:~$ sudo ifdown p3p1 && sudo ifup p3p1
ian072@sundown:~$ sudo ifdown p5p1 && sudo ifup p5p1
ifdown: interface p5p1 not configured
ian072@sundown:~$ sudo nano /etc/network/interfaces
ian072@sundown:~$ sudo ifdown p3p1 && sudo ifup p3p1
ian072@sundown:~$ sudo ifdown p5p1 && sudo ifup p5p1
RTNETLINK answers: No such process
RTNETLINK answers: File exists
Failed to bring up p5p1.