From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com (ext-mx06.extmail.prod.ext.phx2.redhat.com [10.5.110.10]) by int-mx08.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id n9OJH484023953 for ; Sat, 24 Oct 2009 15:17:04 -0400 Received: from mail-gx0-f226.google.com (mail-gx0-f226.google.com [209.85.217.226]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id n9OJGjcq004683 for ; Sat, 24 Oct 2009 15:16:46 -0400 Received: by gxk26 with SMTP id 26so8413240gxk.11 for ; Sat, 24 Oct 2009 12:16:45 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <29ae894c0910241004k327b0ff8w6577b83af3701753@mail.gmail.com> References: <20091023065219.GA8733@maude.comedia.it> <4AE20E43.2060006@worldspice.net> <20091024000642.GA30974@bdmcc-us.com> <29ae894c0910241004k327b0ff8w6577b83af3701753@mail.gmail.com> Date: Sat, 24 Oct 2009 12:16:45 -0700 Message-ID: Subject: Re: [linux-lvm] Total free space using added VGs and LVs From: Lou Arnold Content-Type: multipart/alternative; boundary=0050450295385a0b4a0476b32b97 Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: To: LVM general discussion and development --0050450295385a0b4a0476b32b97 Content-Type: text/plain; charset=ISO-8859-1 Hahaha. Brem, you and I think alike. If you can do it let me know. I don't think people can think of a way to keep the system on-line and yet dismount root so that LVM commands can work on it. If you can make it work, I'll buy you a virtual beer. Regards, Lou. On Sat, Oct 24, 2009 at 10:04 AM, brem belguebli wrote: > It's non sense arguing that LVM is not intended for root due to the > fact that you cannot shrink it (growing online is operational and > works fine). > > This is the only thing that is not allowed, though technically could > it be possible. > > > > 2009/10/24, Lou Arnold : > > Haha, Yes, it would have been nice for someone to have told me about > LVM and > > root. It would have saved literally days of time. But my work is > > experimental and never with production system. In any case, now I know > > better. > > > > As for the LiveCD suggestion, I did not intend to discount it. I had in > fact > > tried it several times, but with some success. It probably just a matter > of > > finger problems for the failures. But I truly expected a graceful > > dismantling process without the need of shutting down the system. > > > > This was in fact a good experience. When you have to dig into things to > > understand why something works or doesn't work, you are always luckier > than > > if things go perfectly right from the beginning. > > > > Thanks to everyone for your help. > > Lou. > > > > > > > > On Fri, Oct 23, 2009 at 5:06 PM, Brian McCullough > wrote: > > > >> On Fri, Oct 23, 2009 at 01:41:23PM -0700, Lou Arnold wrote: > >> > Ryan, Thanks for your suggestion. I know it works, but I had hoped to > >> have a > >> > solution that didn't stop the whole system while I fixed it. > >> > > >> > To Drew: > >> > I think you were quite right when you spoke about planning the file > >> system. > >> > I've come to realize that my question is somewhat naive. One simply > >> doesn't > >> > do what I wanted to exactly because there is no easy way to dismantle > >> > it. > >> It > >> > would be better to partition off some part of the OS drive and add > that > >> to a > >> > new volume group (or a new logical volume group) and mount that under > >> > "/mnt", and then add whatever partitions on new drives to that logical > >> > volume. That logical volume could be dismounted and worked on, whereas > >> > whatever is under root cannot be worked on easily. > >> > >> > >> Lou, > >> > >> I'm surprised that you haven't yet been told that one of the first rules > >> of > >> LVM is "don't use it for root!" Actually, I don't really hold with > that, > >> but it is MUCH more important to plan what you are doing when you do > have > >> an > >> LVM root partition. As you have found, you can not manipulate an LVM > >> partition while it is mounted. ( I know, there are ways for certain > types > >> of > >> filesystems, but in general, the rule holds. ) That is especially true > >> when > >> the partition that you want to manipulate is root ( / ). > >> > >> My general practice is to set up the following list of Logical Volumes ( > >> the minimum which serves for most general purpose machines ): root, > swap, > >> home, usr, var. I generally allocate somewhere around 1G for the root > >> partition. The others are sized appropriately for the environment. > That > >> usually leaves me a lot of free space on modern drives for "data" space. > >> > >> The recommendation that you should find a LiveCD at this point is > probably > >> one that you should respect. Playing with mounted filesystems, > >> particularly > >> root, can rapidly lead you down a very nasty path. > >> > >> > >> Brian > >> > >> _______________________________________________ > >> linux-lvm mailing list > >> linux-lvm@redhat.com > >> https://www.redhat.com/mailman/listinfo/linux-lvm > >> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ > >> > > > > _______________________________________________ > linux-lvm mailing list > linux-lvm@redhat.com > https://www.redhat.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ > --0050450295385a0b4a0476b32b97 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Hahaha. Brem, you and I think alike. If you can do it let me know. I d= on't think people can think of a way to keep the system on-line and yet= dismount root so that=A0LVM commands=A0can work on it. If you can make it = work, I'll buy you a virtual beer.
Regards,
Lou.

On Sat, Oct 24, 2009 at 10:04 AM, brem belguebli= <brem.bel= guebli@gmail.com> wrote:
It's non sense arguing that = LVM is not intended for root due to the
fact that you cannot shrink it = =A0(growing online is operational and
works fine).

This is the only thing that is not allowed, though tech= nically could
it be possible.



2009/10/24, Lou Arnold <= larnolda1@gmail.com>:
> Haha, Yes, it would have been nice for someone to ha= ve told me about LVM and
> root. It would have saved literally days o= f time. But my work is
> experimental and never with production syste= m. In any case, now I know
> better.
>
> As for the LiveCD suggestion, I did not intend= to discount it. I had in fact
> tried it several times, but with =A0= some success. It probably just a matter of
> finger problems for the = failures. But I truly expected a graceful
> dismantling process without the need of shutting down the system.
&= gt;
> This was in fact a good experience. When you have to dig into t= hings to
> understand why something works or doesn't work, you ar= e always luckier than
> if things go perfectly right from the beginning.
>
> Thank= s to everyone for your help.
> Lou.
>
>
>
> O= n Fri, Oct 23, 2009 at 5:06 PM, Brian McCullough <bdmc@bdmcc-us.com> wrote:
>
>> On Fri, Oct 23, 2009 at 01:41:23PM -0700, Lou Arnold wrote= :
>> > Ryan, Thanks for your suggestion. I know it works, but I= had hoped to
>> have a
>> > solution that didn't = stop the whole system while I fixed it.
>> >
>> > To Drew:
>> > I think you were q= uite right when you spoke about planning the file
>> system.
&g= t;> > I've come to realize that my question is somewhat naive. On= e simply
>> doesn't
>> > do what I wanted to exactly because t= here is no easy way to dismantle
>> > it.
>> It
>= ;> > would be better to partition off some part of the OS drive and a= dd that
>> to a
>> > new volume group (or a new logical volume gr= oup) and mount that under
>> > "/mnt", and then add w= hatever partitions on new drives to that logical
>> > volume. T= hat logical volume could be dismounted and worked on, whereas
>> > whatever is under root cannot be worked on easily.
>>= ;
>>
>> Lou,
>>
>> I'm surprised th= at you haven't yet been told that one of the first rules
>> of=
>> LVM is "don't use it for root!" =A0Actually, I don&#= 39;t really hold with that,
>> but it is MUCH more important to pl= an what you are doing when you do have
>> an
>> LVM root = partition. =A0As you have found, you can not manipulate an LVM
>> partition while it is mounted. ( I know, there are ways for certai= n types
>> of
>> filesystems, but in general, the rule ho= lds. ) =A0That is especially true
>> when
>> the partitio= n that you want to manipulate is root ( / ).
>>
>> My general practice is to set up the following list of= Logical Volumes (
>> the minimum which serves for most general pu= rpose machines ): root, swap,
>> home, usr, var. =A0I generally al= locate somewhere around 1G for the root
>> partition. =A0The others are sized appropriately for the environme= nt. =A0That
>> usually leaves me a lot of free space on modern dri= ves for "data" space.
>>
>> The recommendation = that you should find a LiveCD at this point is probably
>> one that you should respect. =A0Playing with mounted filesystems,<= br>>> particularly
>> root, can rapidly lead you down a very= nasty path.
>>
>>
>> Brian
>>
>&= gt; _______________________________________________
>> linux-lvm mailing list
>> linux-lvm@redhat.com
>> https://www.redhat.com/m= ailman/listinfo/linux-lvm
>> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
>>
>= ;

_______________________________________________
linux-lvm maili= ng list
linux-lvm@redhat.com
ht= tps://www.redhat.com/mailman/listinfo/linux-lvm
read the LVM HOW-TO = at http://tl= dp.org/HOWTO/LVM-HOWTO/

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