Dracut NM module

[Thomas HUMMEL]

Hello,

looking at how the NetworkManager Dracut module is used (RHEL 8.8 - 
NetworkManager-1.40.16, dracut-049-223) my understanding is that it 
operates at 2 different dracut stages/hooks with 2 different binaries :

1. cmline: creates profiles with  nm-initrd-generator (using some kernel 
cmdline like for instance BOOTIF=

2. initqueue/settled: activates profiles (and quits) with NetworkManager 
--configure-and-quit

I was wondering why it could or should not activate profiles in 1.
If it has something to do with udevd renaming devices, how do generated 
profiles keep up with the renaming anyway ?

Besides, is NM dracut module mutually exclusive with legacy one and how 
to actually know which one is inside an already generated third party 
initialramfs (of course I know how to extract content) ?

For instance, I've encountered an initialramfs which succeeds in having 
network configured but without any args which would make 
nm-initrd-generator create a profile, so I just assumed legacy module 
was at play but this is was just a guess.

Finally, how does NM, which my undestanding is the main purpose of using 
this module in dracut, passes info from intiralramfs to real root ? I'm 
not sure d-bus is on in dracut neither if nm module writes some files to 
real root device ?


Thanks for your help



-- 
Thomas HUMMEL
HPC Group
Institut PASTEUR
Paris, FRANCE