@Geert > It is "netinst" that you are looking for. I am using netinst. Appreciate the detailed steps listed, but with all due respect, my question was about how to make the installer install the base system from the mirror and not the installation media. The listed steps don't seem to help with that.
@Andrew @Holger @Steve I take that as it's not possible to force the installer to install the base system from the mirror? I guess the netboot image probably does something special. Guess I'll just have to let the installer upgrade then. @Andrew > an autoremove would remove the fallback kernel since you didn't boot from it I'm not sure that's the case. I tried running "apt-get autoremove" in a newly installed Debian 11 with multiple kernels in /boot, no packages got removed. `apt-cache rdepends --installed linux-image-5.10.0-10-amd64` (which was the old kernel) showed "linux-image-amd64" depended on it, so it was not removed. "apt-cache depends --installed linux-image-amd64" showed it depended on "linux-image-5.10.0-11-amd64". Regards, Glen