1.Which platform are you building for?
ESP8266 2.What is the size of fw.zip ?
933KB 3.Can you flash it successfully?
Yes. 4.Do you build a custom firmware or one of the demos?
Smartlight demo 5.BTW, the syntax of your curl line is incorrect. Should be curl -F file=@path_to_the_file . Notice the @
I will check in terminal if I have the @ when sending the curl command. I hope that is a typo mistake in the post and not that is the problem.
I get the same error on mdash.net and curl.
To check if I did something wrong I download again the example from your link, build it with mos build, flash it to a different esp8266(flash is successfully) and try to send it again via OTA.
262144 is the size of the filesystem in the new firmware. The existing one has only 131072.
That means it was built with --build-var BOARD=esp8266-2M and included the boards library.
mongoose-os-smart-light does not include it and it’s built with the default 4M layout.
To build it with 2M layout, either add boards in its mos.yml or use --build-var FLASH_SIZE=2097152.