I'm trying to install a system with an encrypted root system drive and use a keyfile on a usb drive to unlock via luks. I have vfat, nfat, nnls_cp437, and nnls_iso8859_1 modules set to load in the initramfs. I have luks setup with a keyscript that does run during boot time and the initramfs with these added modules is the one being used.

The problem is the keyscript is being run before the system has a chance to recognize the usb drive. Using the sleep command doesn't seem to work to delay the script. I've even tried using "busybox sleep 60" and it doesn't work either. I've tried long delays like 60 seconds so I could be sure they are runnig or not. The script seems to immediately execute so I'm sure there's not 60 second delay. Then when it fails to find the usb drive it fails over to a prompt for the password. While sitting at the prompt I can then see the usb drive being recognized by the system. I see the dmesg style info come up on the screen recognizing the drive. If the script would delay for even 10 seconds it would be able to execute after the system found the usb drive, mount the usb drive and get the key.

What am I missing that will allow the sleep command to work to delay the script from trying to mount a usb drive it hasn't found yet? Or can I delay the execution of the script itself by having the system try to mount the encrypted root fs later after the usb has been found? Is there a way to specify the order these things happen in the initramfs similar to how you can number init scripts on the system itself to execute in a certain order?

Let me know any other info you need to help with this. I'd appreciate any insight anyone may have to this.

Make sure your usb_storage module is either builtin or loaded by initramfs.

Another thing you could try is to set the computer to boot from USB. Put grub on the USB drive but set up the menu to get the kernel and root filesystem from HDD.

I've set the modules to be in the initramfs by adding them to the /etc/initramfs-tools/modules file. Then the script I use checks for them and modprobes them if they're not loaded.

The problem is that the script runs and doesn't respect the sleep command and doesn't slow it's execution to wait for the usb drive to be recognized by the system. I get the script failing to load the usb drive and falling back on it's password prompt on that failure, then I see the dmesg output of the usb drive being recognized far too late. Well after the script has tried to load it. That's why I need the script to sleep for a few seconds so the system can find the drive, then try to mount it.

My final option will be to put grub on the usb drive and boot from it. Any good tutorials on that? I've never done it before.

Try loading the modules you need with script itself like:

modprobe ehci ohci uhci usb-storage and other needed modules

you can see modules dependency using modinfo command

That's what my script already does, it modprobes the modules that are needed. First it checks for them and then modprobes them. Then I commented the check out and it just modprobes them.