Cannot sysupgrade GL.iNet AR750S (and GL.inet AR300M neither) to 19.07.4

I tried to sysupgrade an Gl.iNet AR750S router with the 19.07.4 vanilla OpenWrt firmware, but it fails.

root@GL-AR750S:~# sysupgrade -v /tmp/openwrt-19.07.4-ar71xx-generic-gl-ar750s-squashfs-sysupgrade.bin
Invalid sysupgrade file.
Image check 'platform_check_image' failed.
root@GL-AR750S:~# sha256sum /tmp/openwrt-19.07.4-ar71xx-generic-gl-ar750s-squashfs-sysupgrade.bin
f37cfdd1a5e72fa6680e6b33804a5866d1c58cb0dbedd0f2b86ccbb9f3576d92 /tmp/openwrt-19.07.4-ar71xx-generic-gl-ar750s-squashfs-sysupgrade.bin

The sha256sum is the same as noted in the directory.

I had the same problem with newer Gl.iNet AR300M routers lately. I could sysupgrade two from an older batch, but not three from a newer one.

What do I do wrong?

This looks like your device/platform is not recognized correctly. I had sth. like that on my own built images in the past due to update mismatch in my kernel/feeds tree for a different device.
So it could be that there went sth. wrong during the build process from build bot? oO
But that has to be juged be a more qualified board member here.
So just a small bump instead of a solution. Sorry.

I'm pretty sure the AR750S cannot be upgraded to 19.07.x. The kernel of 19.07 was increased from 2M to 4M; the original 2M kernel space cannot be upgraded to 4M kernel. I could be mistaken, of course.

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Uh, what? It's a pretty recent device with 16MB Flash and 128MB RAM which comes with OpenWrt 18.06.0-rc1 pre-installed. If such a device isn't upgradeable, which one is?

Might be worth getting in touch with the GL-inet support team. There are a few discussions about 19.07.x support for the AR750S on their forum; e.g.

Oh. Thanks for that information.

What bugs me most is I have the same problem with some newer AR300M. I could upgrade a previous batch through their U-Boot. But not a newer batch. Such regressions are awful. Any recommendations which small low-cost router to buy as an alternative then?

For hardware recommendations please open a new topic in the Hardware Questions and Recommendations category of this forum.

Please see before asking for recommendations. This way you will get better recommendations and come to a quicker solution.

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this has been handled on the master branch, see commit below. If you want to update it now you either have to backport some commits and make your own image, or just flash a snapshot image. Version 20 will have all these fixes in the new ath79 target.

For AR750S the story is a little more complex...
Read the commit messages and comments carefully, there is an issue with kernel size, you may have to update the uboot image.

If you update u-boot using openwrt make sure to save a backup of the original, and after writing to it verify with checksum of the mtd partition (probably /dev/mtd0) before you reboot or there is a chance you end up with a bricked board.

Thanks, @mpratt14; hadn't spotted that (and was under the impression that the AR750S had been dropped from the OpenWrt tree). I'll point the Gl-iNet support team to your post to see if they're aware.

Thanks for that information. I will try it for the AR300M then.

Just created an account here to let you know that my AR750S is rolling 17.04 without any problems, I sysupgraded few hours ago just after I saw this thread to check if I would've been able to upgrade form 17.03 or not.
Still on ar71xx though. But it seems still stable. I use it as my main router + wireguard VPN entry.
I knew for a while it would get to ath79 before 20.0 because of that kernel size issue (i've been following openwrt and gluon git in fear that the AR750s would be dropped)so mine has been 24/7 since 17.01 and sysupgrade each time until now.

All that to say I find it strange you weren't able to install the latest 17.04 :thinking:

I do own a AR300M, I will check it runs 17.04 later today, I keep you posted.

You are mixing the ancient 17.01.x with the recent 19.07 branch.

  • 17.01 is the third-last release branch, no longer supported. 17.01.7 from June 2019 is the last maintenance version.
  • 19.07.4 is the current release, made from the 19.07 branch with two years newer code than 17.01.

There is no "17.04"

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Sorry bad typo.
But I am using 19.04 on my AR750S, screenshot from my smartphone (I'm at work)

Yeah keep in mind that devices never get dropped, only disabled (and hopefully it is temporary)

From reading the commit comments I think GL.inet made a new uboot image because of this but I could be mistaken, never hurts to reach out to support anyway.