I am trying to build a custom image (firmware) for my TP-Link (AC1750) C7 version 5.
Which of the following image builders should I use?
https://downloads.openwrt.org/snapshots/targets/ath79/generic/openwrt-imagebuilder-ath79-generic.Linux-x86_64.tar.xz
http://downloads.openwrt.org/releases/19.07.8/targets/ath79/generic/openwrt-19.07.8-ath79-generic-tplink_archer-c7-v5-squashfs-sysupgrade.bin
Let me explain how I got to those candidates.
What told me that I needed an "image builder" was the following bit from this user guide:
You can download an archive that contains the Image Builder, it is usually located in the same download page where you find the firmware image for your device.
For example, this is the page where you can download all firmware images for ath79/generic devices: https://downloads.openwrt.org/snapshots/targets/ath79/generic/ and you will find a openwrt-imagebuilder-ath79-generic.Linux-x86_64.tar.xz archive with the image builder in it. Also, it is always created by the build system because it is needed to create the image file. If the option “Build the OpenWrt Image Builder” is enabled, the image builder will be generated in the same folder you find firmware images (source/bin/targets/xxx
) and you can use it to create more images from the packages you obtained during compilation.
For me, the "the same download page where you find the firmware image for your device" was this page: https://openwrt.org/toh/tp-link/archer_c7
That page didn't have anything like a file named "tar.xz"; but it did say (for my version of the router model):
Target: ar71xx-ath79
If I ignore the bit about "ar71xx", the "ath79" was exactly the thing the user guide used as example! So maybe the image builder mentioned in the example is the one I should use?
But I have the following bit from this post to confuse me:
I don't use the image builder as I build from source, but given that the Archer C7v5 appears to be supported on the ar71xx target for 18.06.4
http://downloads.openwrt.org/releases/18.06.4/targets/ar71xx/generic/openwrt-18.06.4-ar71xx-generic-archer-c7-v5-squashfs-sysupgrade.bin
that appears to be a correct image builder to use.
So an image builder could be either a generic "tar.xz" file or a highly specific "bin" file for the model and version? If so, I should rather use the latter?
I realize that, at the top of this post, I linked items on a "snapshots" and a "releases" page. I see that either of those pages have generic "tar.xz" files and bin files for C7 version 5. I believe my question is about the tar.xz vs. bin distinction (which should be my image builder), not about snapshots vs. release.
I have created a long post to show what sort of newbie I am.
You can also see this post on my motivation for building an image.