An image built with no extra packages

[manywrt]

Suppose I start with the image builder off a particular download page, e.g.

https://downloads.openwrt.org/releases/19.07.8/targets/ath79/generic/

set PROFILE to a particular model (e.g. TP-Link C7 v5), add/subtract no packages, add no config file, and run make image: Does that give me an output identical with a bin file downloadable from that download page for that model?

If yes, is the output identical with the factory or the sysupgrade bin?

In other words, having created a bin by running make image, could I use the output for flashing a router running on either a factory firmware or another version of OpenWrt?

If the output of make image is a sysupgrade bin, then preparatory to using it, I would first have to flash the router with a factory bin?

If the "no packages, no files" output of make image is not identical with a downloadable bin for particular model of router, then how is it going to be different?

Obviously, I am not trying to use the image builder just so I could create, with more difficulty, a bin that could have been simply downloaded. I am trying to understand the image building process, the nature of its output, etc.

I am new to OpenWrt and have never created an image. Please set me straight if the questions are way off.

[hnyman]

@manywrt

set PROFILE to a particular model (e.g. TP-Link C7 v5), add/subtract no packages, add no config file, and run make image: Does that give me an output identical with a bin file downloadable from that download page for that model?

In principle, yes.

I do not use the imagebuilder myself (as I use the full toolchain), but it might give you both factory and sysupgrdae images.

• Sysupgrade images are used for upgrading a router already running OpenWrt from that Openwrt using sysupgrade
• Factory is used to install OpenWrt for the first time using OEM tools (OEM firmware, OEM TFTP recovery, etc.)

For most routers, factory is identical to sysupgrade but has extra packaging to make it compatible with the OEM flash routine validity checks.

The practical reason to use imagebuilder is to add some packages to the firmware. If you just want the default packages, there is not much need for it (in the release branches like 19.07). Master buildbot image do not contain LuCI GUI, so adding the GUI might be a valid reason to use imagebuilder with the master branch.