CentOS - Sep 2010 - couple questions about initrd.img

here's hoping this is on topic.  as part of the extra goodies i'm
going to give my RHEL/centos basic admin class this week, i'm going to
get them to open up the standard initrd.img file and see what's
inside.  i just did that myself and have a couple simple questions.

  first, while the cpio archive physically contains a number of basic
/dev special files, the top-level "init" script runs "mknod"
to create
them all, anyway.  not a big deal, but is it fair to say that
populating the initrd.img with those initial /dev files is redundant
since init creates them all, anyway?

  also, i note that that "init" script appears to call a couple
scripts/commands that don't exist in the initrd, such as hotplug and
mkblkdevs.  again, not a big deal but if i show the students what's in
that initrd, chances are someone's going to notice the above and ask
about it, so i might as well have an answer.  thanks.

rday

-- 

=======================================================================Robert P.
J. Day                               Waterloo, Ontario, CANADA

        Top-notch, inexpensive online Linux/OSS/kernel courses
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========================================================================

From: Robert P. J. Day <rpjday at crashcourse.ca>
>   first, while the cpio archive physically contains a  number of basic
> /dev special files, the top-level "init" script runs
"mknod"  to create
> them all, anyway.  not a big deal, but is it fair to say  that
> populating the initrd.img with those initial /dev files is  redundant
> since init creates them all, anyway?
Maybe needed before the top-level "init" script...?
Or do you mean the mknod is called before the extraction of the initrd.img?
>   also, i note  that that "init" script appears to call a couple
> scripts/commands that don't  exist in the initrd, such as hotplug and
> mkblkdevs.  again, not a big  deal but if i show the students what's in
> that initrd, chances are someone's  going to notice the above and ask
> about it, so i might as well have an  answer.  thanks.
https://bugzilla.redhat.com/show_bug.cgi?id=201237

JD