[systemd-devel] what dependencies does systemd itself have on underlying system?

[John Lumby]

Mike Kazantsev wrote:
 >
 > Some stuff is listed in the README file (REQUIREMENTS and WARNINGS
 > sections), but it doesn't really covers all possible misconfigurations,
 > of course.
 >
 > To figure out what exactly goes wrong, I think it might help to disable
 > pymouth, remove "quiet" from kernel cmdline and add somehing like
 > "systemd.log_level=debug systemd.log_target=kmsg" there (see systemd(1)
 > and kernel Documentation on cmdline parameters).
 >

Thanks Mike.    I tried that but there were no log messages.    But then 
it dawned on me what the cause of the problem (with custom kernel) was :
systemd was reporting this on the console:

         Failed to mount /dev: No such device

This made no sense to me until I checked what the errno corresponding to 
this  and what causes that errno from a mount() :

      ENODEV filesystemtype not configured in the kernel.

So that was my "misconfiguration".       Mentioning it in case anyone 
else hits this and is baffled.

Also  -  just a thought  -  maybe systemd should treat this as a warning 
rather than a showstopper and try to carry on  (i.e. use the existing 
/dev structure);    in my case it would (I believe) have come up ok plus 
or minus a few trivial parts.     And,  yes  -  now I see devtmpfs is 
stated in the README REQUIREMENTS    :-X

Cheers,   John