Debugging Early Dracut Problems

I've recently been trying to enable the Dracut deploy ramdisks I posted about earlier for RHEL7. I've been running into some issues that weren't present on the other platforms I've tested so far, and because of that I want to ask for some help from some Dracut experts. Unfortunately, the problem I'm having occurs so early in the Dracut boot process that it hasn't started any device management yet, so attaching a disk to collect logs doesn't work immediately.

To get the debug disk recognized, I had to run /lib/systemd/systemd-udevd & and then modprobe virtio_blk (the disk was attached as a virtio device, modprobe the appropriate module for the type of device you're using) from the Dracut emergency console. Once I did that the disk was recognized correctly and I was able to collect the debugging data I needed.

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