kernel modules and udev

[Roger Oberholtzer]

I have a situation where I am wanting to ensure that removable SATA
disks maintain a consistent mount point, no matter which disks are
present. The classic problem.

Here is my twist on it:

If I have the sd_mod module loaded as part of initrd, the udev calls are
not made. The disks are located and entries are made in /dev in the old
fashioned way (first disk is /dev/sda, and so on). If I wait a bit and
load sd_mod by hand, then the udev calls are made.

Is udev not ready before any drivers that would add disks are loaded?
Isn't udev compiled into the kernel (not a module)? Is it that udev
needs files on the disk that may not be mounted yet, so they hold off
calling it? In my case, the SATA disks have nothing at all to do with
the OS. They are data collection disks.

Any thoughts? I did not find anything useful when searching. I am using
ThinStation (www.thinstation.org) for this. I have of course asked on
their mailing list. I asked here as well since there is a broad range of
experience here. I am curious if this is a general problem or something
specific to ThinStation.

-- 
Roger Oberholtzer
OPQ Systems AB