Hi, First I suggest to move this thread over to centos list instead of centos-devel. I think it's more appropriate there. > 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. What I'm wondering here is, do you see the hangs because of wpa_supplicant was terminated and therefore also the wireless interface is down, or do you see the hangs because networking is already completely down. If it is because wpa_supplicant gets terminated, then maybe it would be possible to terminate wpa_supplicant in a way that it lets the wireless interface still up and functional at least for a certain amount of time. I don't know wpa_supplicant good enough but I think maybe it is not always needed to be alive for the wireless interface to work. Otherwise, I guess it's more a question for the systemd developers than for CentOS or Linux in general. Regards, Simon