[linux-lvm] how can I init LVM on software RAID ?

[Jürgen Frank]

Yes, the init script is running before the LVM should start. The
Raid-System startup, too, but not correctly. (one of the mirror disk
failed)

> Joe Thornber wrote:
> 
> Hi,
> 
> Are the software raid init scripts being called before the LVM ones ?
> 
> - Joe
> 
> On Tue, Jan 16, 2001 at 08:16:15AM +0100, Jürgen Frank wrote:
> > Hi everyone, Hi Chris
> >
> > ok, I think I have a little solution for my problem with the LVM over
> > SoftwareRaid. It's seems to
> > work with the new beta version (sorry I don't try the patch for the
> > 0.9).
> > So we have only one little problem, if we boot our system the raid1
> > (mirror)-system don't start correctly.
> > (on off the mirror disk isn't running). In that case the lvm don't start
> > too !?
> >
> > But I think that's more a problem of the SoftwareRaid , possible it's a
> > hardware failure of the disk or the disk have a very high startup time.
> > But I don't understand why lvm don't startup, normally this is a
> > transparenc fault , or ?
> >
> > byebye Juergen
> >
> >
> > >Chris Worley wrote:
> > >
> > > Jürgen,
> > >
> > > You are correct.  That is a very good question (and valid for this
> > > newsgroup).  I don't have an answer.  I've seen the documentation that
> > > says you can make raid 10 & 50 (etc...) by mixing MD's under PV's, as
> > > well as making VG's out of LVM's (but why?).  I've also seen errors if
> > > I haven't set my PV's partition to 8e... and there's no way to fdisk
> > > an MD (to set the partition type).  I would worry about the
> > > performance of two layers of software overhead below the file system.
> > >
> > > I had barely crawled out of bed when I saw your post and thought "I
> > > can help a newbie".  This is not a trivial question, I was wrong ;)
> > >
> > > Chris
> > >
> > > Jürgen Frank wrote:
> > >
> > > > Chris Worley wrote:
> > > >
> > > >> Jürgen,
> > > >>
> > > >> "md" and "lvm" are two different ways of making a software raid.
> > > >>
> > > >> lvm only does raid0.  The main purpose of LVM is to allow you to manage
> > > >> disks underneath the file system... adding and removing disks
> > > >> dynamically.
> > > >>
> > > >
> > > >
> > > > Jep, that's the point why I want to use this two systems. So I want to
> > > > create a RAID 1 / 5 system and on the top I put the LVM. With this
> > > > method I have a good system with snapshot and enlargment feature !!!
> > > > And if I read all the docu (the howto, the pdf from sistina) lvm works
> > > > fine with the md - drives. But, that is the point which I can't follow
> > > > in the moment. Because I can't make partitions on a md drive and LVM
> > > > need this partitions ...
> > > >
> > > >
> > > >
> > > >
> > > >> There should be HOWTO's for md in your /usr/doc area.  The LVM newsgroup
> > > >> is not a good place to ask MD related questions.  There are a few
> > > >> "howto's" for LVM:
> > > >>
> > > >> http://www.sistina.com/lvm/Pages/howto.html
> > > >>
> > > >> I like:
> > > >>
> > > >> http://www.ds9a.nl/lvm-howto/HOWTO//cvs/lvm-howto/lvm-howto.html
> > > >>
> > > >> Chris
> > > >>
> > > >
> > > >
> > > > I read all this docu, but I can't find any help for a system LVM over
> > > > MD-Drives (Software RAID) !!!
> > > >
> > > >
> > > > Juergen
> > > >
> > > >
> > > >> Jürgen Frank wrote:
> > > >>
> > > >>> Hi !!
> > > >>>
> > > >>> I want to create the following system :
> > > >>>
> > > >>> I use the new kernel (2.4) and I want to use the software raid and the
> > > >>> lvm,
> > > >>> but my problem is... how ?
> > > >>>
> > > >>> I can't find a step by step documentation and all what I try don't work.
> > > >>>
> > > >>> So what did I done :
> > > >>>
> > > >>> * create a mirror system with software raid (last version), after this
> > > >>>   step I have a good raid system with the drive /dev/md0
> > > >>>
> > > >>> * normally now I need to create a partition on the drive , but I read in
> > > >>> the raid docu that the md-drives don't support partitions !!!
> > > >>>
> > > >>> But, without a partiton of the type 0x8e I can't run vgscan and
> > > >>> pvcreate...
> > > >>>
> > > >>> So, can anyone help me ?!
> > > >>>
> > > >>> Juergen
> > > >>>
> > > >>> (sorry for the bad english)
> > > >>> _______________________________________________
> > > >>> linux-lvm mailing list
> > > >>> linux-lvm at sistina.com
> > > >>> http://lists.sistina.com/mailman/listinfo/linux-lvm
> > > >>
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