Bug#915088: multipath-tools: installing multipath-tools will force dracut to be removed while it shouldn't.

2018-12-03 Thread LAHAYE Olivier
I understand, I don't want to break things for sure.

In the meantime, I think that dracut native multipath module has the logic to 
handle stackable storage, though, of course, on Debian nobody can test as both 
dracut and multiupath-tools can't be installed together for further testing 
debugging.

On my side, (Systemimager), I made multipath-tools optional (dracut generates a 
warning telling it can't load the multipath module because multipathd binary is 
not found), and that's ok for those who don't need multipath)

It's up to you to decide what is the best for Debian.

My though (outside this bug reporting) is that it would be a good step forward 
for Debian to switch from old initramfs-tools to modern dracut.

Cheers,

Le 01/12/2018 05:55, « Ritesh Raj Sarraf »  a écrit :

Hi Olivier,

I am not denying any of what you have said below. Dracut may be a great
tool. But unfortunately, it does not have the uptake in Debian, that
initramfs-tools has. Just look at the popcon stats.

multipath-tools needs tight integration with the plumbing layer to
ensure you have a stackable storage. For Debian, the work so far has
been done integrating it with initramfs-tools.


I am not opposed to adding dracut as an option. It is just that I have
never worked on it. Nor have any users/developers ever reported about
its integration here.

If dracut can serve as a drop-in replacement, I don't have any problem
adding it as an OR dependency in `sg3-utils-udev` package.


On Fri, 2018-11-30 at 16:13 +, LAHAYE Olivier wrote:
> Dracut is the only tool to create initramfs on many distros and it
> works fine with multipath so far. Dracut is to initramfs-tools what
> systemd is to basic initscripts.
> Dracut is modular and event driven while initramfs-tools is
> monolithic and linear static.
> 
> If you look at /usr/lib/dracut/modules.d you'll notice that a module
> already exists for multipathd. (/usr/lib/dracut/modules.d/90multipath
> and /usr/lib/dracut/modules.d/90multipath-hostonly)
> 
> man dracut
> man dracut.modules
> man dracut.cmdline
> 
> See also the module-setup.sh in both 90multipath and 90multipath-
> hostonly modules
> 
> Dracut is really a wonderful piece of code that is really easy to
> understand and that can create really powerful ramfs images.
-- 
Ritesh Raj Sarraf | http://people.debian.org/~rrs
Debian - The Universal Operating System




Bug#915088: multipath-tools: installing multipath-tools will force dracut to be removed while it shouldn't.

2018-11-30 Thread LAHAYE Olivier
Dracut is the only tool to create initramfs on many distros and it works fine 
with multipath so far. Dracut is to initramfs-tools what systemd is to basic 
initscripts.
Dracut is modular and event driven while initramfs-tools is monolithic and 
linear static.

If you look at /usr/lib/dracut/modules.d you'll notice that a module already 
exists for multipathd. (/usr/lib/dracut/modules.d/90multipath and 
/usr/lib/dracut/modules.d/90multipath-hostonly)

man dracut
man dracut.modules
man dracut.cmdline

See also the module-setup.sh in both 90multipath and 90multipath-hostonly 
modules

Dracut is really a wonderful piece of code that is really easy to understand 
and that can create really powerful ramfs images.

Cheers,

Le 30/11/2018 16:01, « Ritesh Raj Sarraf »  a écrit :

On Fri, 2018-11-30 at 09:10 +, Olivier Lahaye wrote:
>* What exactly did you do (or not do) that was effective (or
>  ineffective)?
>  Installed multipath-tools using:
>  apt-get install --no-install-suggests multipath-tools
> 
>* What was the outcome of this action?
>  dracut was replaced with initramfs-tools because sg3-utils-udev
> is
>  required by multipath-tools and sg3-utils-udev conflicts with
>  dracut
> 
>* What outcome did you expect instead?
>  It should be possible to install multipath-tools and use it with
>  dracut. In other words, it should be possible to do:
>  apt-get install multipath-tools dracut

The problem is that nobody, afaik, has tested the combination of
multipath-tools and dracut together. dracut, afair, claims to be a
drop-in replacement for initramfs-tools. But I am not sure at all.

Right now, multipath-tools has tight integration with initramfs-tools.
Also the sg3-utils-udev package ships in modules to add further
integration.

If dracut can do the equivalent, then we can relax the dependencies.


-- 
Ritesh Raj Sarraf | http://people.debian.org/~rrs
Debian - The Universal Operating System