Update - Problem Resolved. I had two issues.
1.) The EISY seems to require a reboot - or better yet, power cycle - to recognize the USB FDTI Serial cable AND connect a serial port. During my early attempts to connect the PLM to the EISY, I was not power cycling after inserting the USB Serial PLM cable - and it looked like the EISY was seeing via SSH "dmesg | grep -i usb" commands but there was a message about being disconnected. See below session with disconnected in red
2.) I had a DIY FDTI Serial PLM cable. I tried to save some money, but I spent a lot more of my time and probably should have just purchased the cable from the start.
Thanks to UD tech support for confirming my EISY was operating correctly. Now I need to complete the migration process. Its all downhill from here, right? What could go wrong
I believe if the (disconnected) message shows in response to this command, power cycle the EISY to get it to properly set up the FDTI device and open the UART (com/serial) port.
[admin@eisy ~]$ dmesg | grep -i usb
xhci0: <XHCI (generic) USB 3.0 controller> mem 0x6001100000-0x600110ffff at devi ce 20.0 on pci0
usbus0 on xhci0
usbus0: 5.0Gbps Super Speed USB v3.0
ugen0.1: <Intel XHCI root HUB> at usbus0
uhub0 on usbus0
uhub0: <Intel XHCI root HUB, class 9/0, rev 3.00/1.00, addr 1> on usbus0
ugen0.2: <FTDI FT232R USB UART> at usbus0
Root mount waiting for: usbus0 CAM
ugen0.3: <vendor 0x8087 product 0x0026> at usbus0
uftdi0: <FTDI FT232R USB UART, class 0/0, rev 2.00/6.00, addr 1> on usbus0
ubt0: <vendor 0x8087 product 0x0026, class 224/1, rev 2.01/0.02, addr 2> on usbu s0
ugen0.2: <FTDI FT232R USB UART> at usbus0 (disconnected)
ugen0.2: <FTDI USB-RS232 Cable> at usbus0
uftdi0: <FTDI USB-RS232 Cable, class 0/0, rev 2.00/6.00, addr 3> on usbus0
[admin@eisy ~]$
