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Sat Mar 5 19:55:20 UTC 2022

[root at fixx /root]# dd if=/dev/zero of=/dev/hda3 bs=512 count=1
1+0 records in
1+0 records out
[root at fixx /root]# pvcreate /dev/hda3
pvcreate -- ERROR: "/etc/lvmtab" doesn't exist; please run vgscan
[root at fixx /root]# dd if=/dev/zero of=/dev/hda3 bs=512 count=100
100+0 records in
100+0 records out
[root at fixx /root]# pvcreate -v /dev/hda3
pvcreate -- ERROR: "/etc/lvmtab" doesn't exist; please run vgscan

[root at fixx /root]# vgscan -v
vgscan -- removing "/etc/lvmtab" and "/etc/lvmtab.d"
vgscan -- creating empty "/etc/lvmtab" and "/etc/lvmtab.d"
vgscan -- reading all physical volumes (this may take a while...)

So as you can see i am unable to run pvcreate as it complains about vgscan.
And again it seems that vgscan is never going to return.

Hoping for some pointers

---- On Thu, 19 Sep 2002, James Hawtin (oolon at wrote:

> On Thu, 19 Sep 2002, Ali Zaidi wrote:
> > Hi:
> > I am a novice with LVM but after going through the man pages and howtos i 
> > unable to find a solution to my problem. I am hoping one of you might find 
> > time to point me in the right direction.
> >
> > I am trying to setup LVM on a RH box. I run vgscan before i can create the
> > volumes but it never returns. Same thing happens with lvmdiskscan and 
> > Here is a -v and -d output of vgscan
> Ok and now to try to answer your problem....
> Did you do a pvcreate?
> did the disk have existing data on it?
> Try dd to write /dev/zero to the first bit of the partitions you want to
> put into lvm. then do you vgscan which should then return with an error
> saying it found nothing.... you can then use pvcreate on them
> Of course your LAME disk layout could be confusing lvm in which case as a
> work arround just have one lvm partion and use lvm to allocate the disk,
> which is what you should be doing in the first place!
> ------
> And now a few quick questions and answers....
> Q: I can allocate my disk better than LVM!
> A: No you cannot! or rather you can allocate your disk when you
> first get the machine to produce nice continuous partions. YOU CAN DO THIS
> WITH LVM. If you have a brand new volume group and just add partions to
> it they will be continuous with LVM as well.... Don't trust LVM.. you can
> do a pvdisplay to show you this fact!
> A2: Sure, but what happens if you want to remove 2 partions, that are not
> next door to each other, and them make the one big partion... with fdisk
> its a dd nigtmare... with LVM its easy.
> Q: but how can I move my stuff onto another disk... I use DD!
> A: SO? There is nothing special about lvm devices apart from the fact they
> make things easer for you... You want to work that way, make your new
> device using LVM or fdisk and do your dd! But you could save yourself time
> by using pvmove!
> Q: LVM adds a level of indirection to my disk.. surely its better to use
> the real disk
> A: Theoritically yes... but the translation to where on the disk is a
> calculation done on your computer not on the disk the slowest part of the
> operation is pulling stuff from your disk! Think about is a software raid
> faster or slower? Its faster cos the slow part was the disk and now there
> is more than one disk!
> Q: I like to micromanage my disk...
> A: You can do that with LVM if you like or you can let LVM do the best it
> can for you and use your bonus time to go down the pub.
> James
> _______________________________________________
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> linux-lvm at
> read the LVM HOW-TO at

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