Re: [gentoo-dev] Re: newsitem: unmasking udev-181

[Robin H. Johnson]

On Sat, Mar 10, 2012 at 09:53:25PM -0500, Rich Freeman wrote:
> On Sat, Mar 10, 2012 at 9:27 PM, William Hubbs <williamh@g.o> wrote:
> > here is the udev 181 unmasking news item.
> >
> > If all goes well, this will be committed to the tree ?on 3/14 UTC.
>
> I guess this might be OK for unstable, but before this goes stable we
> really need to improve the docs around this.  As far as I can tell
> neither the genkernel nor dracut docs have specific instructions about
> how to handle mounting /usr.  Since having a separate /usr is often
> the result of having a more complex configuration (nfs, lvm, mdraid,
> etc), instructions explaining how things work and how to handle
> variations is pretty important.  Perhaps genkernel automagically does
> the right thing in some cases, but I know that dracut does not unless
> you properly configure it.  I doubt either tool will handle more
> complex situations without some scripting.
With the new versions of genkernel as specified in the news item, you do
NOT need any specific instructions about /usr. Just upgrade your
genkernel and openrc, and (re)build your initramfs, done.

> Again, this is likely more of a concern before this is stabilized.
> However, knowing what I went through to get my bind-mounted /usr on
> LVM+mdraid working with dracut, I can imagine that any unstable users
> with tricky setups could face a fun weekend.
Your bind-mount /usr and a symlink at /usr to /home/usr are the most
troublesome cases for genkernel that I'm aware of.

For both of those cases, just add extra lines to /etc/initramfs.mounts
should suffice your needs. I realized that I hadn't given much
documentation in that file, so I added a much more detailed example in
genkernel-3.4.25-r1.

If you could please test your LVM+MDRAID+bind-mount setup with
genkernel-3.4.25-r1, I'd like to know your results.
genkernel --lvm --mdadm should cover most of it.

-- 
Robin Hugh Johnson
Gentoo Linux: Developer, Trustee & Infrastructure Lead
E-Mail     : robbat2@g.o
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