This topic has been addressed many times before but after a year and some healing of the fracturing in the YUN architecture, I have to ask again if Arduino will get some sense and release a real fix to the Arduino YUN firmware so that there can be some consistency. The .ORG YUN board came with some new features notable in the hardware, but, with LININO in lieu of OpenWrt its man-made hell for guys trying to broaden their projects, The 2015-16 firmware changes in LININO are just nothing but pain. And not my woes are not uncommon -
I have three YUNs from late 2014, early 2015, all still working OpenWrt in the field or bench. I bought two more a year later (surprise they come with a new OS) and they have been a pain. First I got a defective one with no USB, and then the next one had boot and/or password issues that others have been unable to solve.
The firmware upgrade try failed on ONE so it may be bricked now. It won't TFTPUtil. Wierd though WinSCP can move files over ethernet. And the serial terminal works. I can't logon to the OS at the wired Ethernet; WIFI doesn't come up. I may try the suggestion of 1.4.1 version as that is probably what I have on my others.
cd /mnt/sda1 sysupgrade -n -v openwrt-ar71xx-generic-yun-16M-squashfs-sysupgrade.bin
I have one .ORG YUN that is still working out of the box that will never get upgraded or used unless we can get them all the same and loaded with Openwrt and 1.5.3 (or 1.4.1 to try tmrw) or 1.6.2?? - I hope. "ShapeShifter" addressed this about a year ago after I made similar comments. I have been hoping there would be some progress to get us all of us on the same Arduino.CC page. Would someone do this as a service? Seems so many users have an approach that works for their special situations but none that is clear enough.