Hi,
I've got a task to have a small number of laptops netboot Linux over WiFi. The kernel is loaded off the USB stick of cource, it's off topic for now.
The WPA-supplicant daemon is started early by dracut off initrd. It works. Mostly.
The problem is that upon shutdown systemd terminates all the processes FIRST and unmounts filesystems NEXT.
Guess what? Upon termination, wpa-supplicant brings the wireless interface down and the system hangs being unable to unmount now-defunct NFSroot.
There were some discussions regarding similar matter and there's even the RH Errata: https://access.redhat.com/errata/RHBA-2018:2447 But I'm woking on a fully updated CentOS Linux release 7.8.2003 and nevertheless I've got the problem.
I don't have rights to see the BZ. https://bugzilla.redhat.com/show_bug.cgi?id=1593649
I'm deciding to use a quick and dirty hack to do a totally ungraceful shutdown/reboot: https://unix.stackexchange.com/questions/533307/systemd-fails-to-umount-manu...
Any better ideas?
Best regards, Dmitry Mikhailov.