downloaded the latest image but sysupgrade says
Invalid image type.
Image check 'platform_check_image' failed.
This is a v1 yun running latest arduino.cc image which is attitude adjustment and so very old, can anyone confirm if the bridge library works OK on the stock 18.06 image and if so how do I upgrade?
do I have to use the uboot upgrade method?
edit:
do a backup first. this page " Create full MTD backup" script works OK
https://openwrt.org/docs/guide-user/installation/generic.backup
A lot more reading around led me to yunupdater
https://www.arduino.cc/en/Guide/YunUpdater
make sure the host machine is not behind a firewall between itself and the yun, as the yun tries to connect to the host ip you specify to do the downloads I guess, even ufw on the host will block it if you have that set up!
I Think you can stick with the ip address yunupdater chooses for the yun even if it is not the right current address, though cannot confirm that. (i think it wants an address that does not exist on your lan)
so that takes it to LEDEYun 17.11 which is quite an advance, but... The activity LED's do not work the same anymore. Which may be problematic in as much as what gpios on the atheros is it trying to drive?
edit2:
Or just a deliberate change on how the led's work... toggling an LED at a high rate on a slow mcu itself may be a factor that further slows the MCU... just observed on the yun that using overlay file system slows it down (observing using top), and running luci realtime network graphs while doing an scp slows transfer rate from 1mb/s with no luci client to 750kb/s doing transfer with luci realtime network graph running in browser... what the linux/wifi mcu of the yun is scaled to be able to do... is good enough for a sensor hub with a few low traffic wifi nodes and it's own set of sensors and indicators....
great! awesome!
edit 3:
so it seems the ddwrt method of installing to /opt on an sd/usb/ssd is the best, no need for extra package for overlay file system swapping out possibly faster built in cmos entirely to a slower medium (ok the ssd case is probably the case where it is ok to use overlay file system)
another post on this forum has a script to do symlinks to main storage for packages installed in /opt, a built in method that does that with a flag to opkg install seems best!
could be actually mounting a vfat file system for the arduino to use, is what adds the extra load? (something is!)
and the ledeyun seems to have bluetooth built in to image when it does not have bluetooth as standard in hardware.
Conclusion
LEDEYun, being the official arduino release for the Yun Rev 2 has everything someone without in depth knowledge of openwrt might need without having to invest lots of time learning about openwrt. Including Bluetooth which might be useful for the mobile phone generation by just plugging in a usb bluetooth dongle
The yunupdater works OK, the disk space expander/external-fs setup is simple enough for the end user, though not sure if you want a swap file setting up... but simple enough to comment out that line in the source code.
And looks like the github repo for LEDEYun has the stuff required to compile a custom version which if I get time I will have a look at doing, sure you can make the yun significantly faster and have more free memory by removing stuff you personally do not need.
Excellent!