[linux-lvm] Reducing/Resizing LVM where "/" filesystem is included in the LVM
fromkth+lvm at fastmail.fm
fromkth+lvm at fastmail.fm
Mon Jan 31 00:38:45 UTC 2005
I am able to partialy solve my problem, so still needs help to complete
it. This may be help full for newbie like me, so i am writing the
steps here.
So first let me define again what i wanted to do.
fromkth+lvm at fastmail.fm wrote:
> Hi,
>
> I am a newbie to linux and I have XP and FC3 on my 30GB HD. I have
> searched through internet to find out how to reduce logical Volume
> based on LVM2, but as my situation is quite different hence could not
> find out any solution. I have total 3 Primary partitions and one
> extended partitions. first 3 primary partitions are
> NTFS(XP),FAT32(data) and NTFS(data) respectively. Extended partition
> contains two partitions, linux boot and linux LVM. Linux LVM contains
> one Group Volume which contains two Logical Volumes. One Logical
> Volume has / root file System and other Logical Volume has SWAP space.
>
>
> Here is the output of fdisk -l and contents of /etc/fstab
>
> fdisk -l
> =======================================================================
> Disk /dev/hda: 30.0 GB, 30005821440 bytes 255 heads, 63 sectors/track,
> 3648 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes
>
> Device Boot Start End Blocks Id System
> /dev/hda1 * 1 637 5116671 7 HPFS/NTFS
> /dev/hda2 638 1274 5116702+ c W95 FAT32(LBA)
> /dev/hda3 1275 2546 10217340 7 HPFS/NTFS
> /dev/hda4 2547 3648 8851815 f W95 Ext'd(LBA)
> /dev/hda5 2547 2559 104391 83 Linux
> /dev/hda6 2560 3648 8747361 8e Linux LVM
> =======================================================================
>
>
> cat /etc/fstab
> ==========================================================================
> # This file is edited by fstab-sync - see 'man fstab-sync' for details
> /dev/VolGroup00/LogVol00 / ext3 defaults 1 1
> LABEL=/boot /boot ext3 defaults 1 2
> none /dev/pts devpts gid=5,mode=620
> none /dev/shm tmpfs defaults 0 none
> /proc proc defaults 0 none /sys
> sysfs defaults 0 /dev/VolGroup00/LogVol01 swap swap
> defaults 0
>
> /dev/hdb /media/cdrom auto pamconsole,fscon-
> text=system_u:object_r:removable_t,ro,exec,noauto,managed 0
>
> /dev/fd0 /media/floppy auto pamconsole, fscontext=system_u:object_r:r-
> removable_t,exec,noauto,managed 0 0
>
> /dev/hda1 /mnt/win_ntfs_c ntfs ro,defaults,umask=0222 0 0
> /dev/hda2 /mnt/win_fat32_d auto ro,defaults,umask=0222 0 0
> /dev/hda3 /mnt/win_ntfs_e ntfs ro,defaults,umask=0222 0 0
> ================================================================================
>
> Now I want to free some space from the linux LVM(hda6) and create a
> FAT32 partition as hda7.
>
> So how to reduce that LVM?
So Robin Suggested:
======================
I suggest you use qtparted. Basically you need to:
1. Resize /
2. Move the swap volume back so it is adjacent to / (as it is swap, you
could just run swapoff, delete the volume, and then recreate it.)
3. Reduce the physical volume size
I don't know if qtparted can do step 3 but it can do steps 1 and
2, I think.
Oh and of course, to do this, you must be running a separate copy of
Linux
- like a live CD. Knoppix, for example, boots with usually no user
intervention required, and contains qtparted and everything it needs.
My Reply
> fromkth+lvm at fastmail.fm wrote:
>
>> I ran Knoppix Live CD 3.7 which has qtparted 0.4.4 and it does not
>> recognizes the linux lvm partition and shows it as unknown
>
> [...]
>
>> so the question remains how to do it.
Sam Vilain wrote:
>
> The knoppix CD also has the commandline lvm utilities and ext2resize
> binaries. Have fun reading the manpages for vgscan, vgchange,
> ext2resize, lvreduce, pvmove, vgreduce, pvremove, fdisk, pvcreate,
> vgextend, and pvmove. Not necessarily in that order.
>
> HTH.
My Reply:
==============
Knoppix 3.7(whether you boot in 2.4 or 2.6 kernel) does not have lvm
utilities or ext2resize binaries, so i tried to install over from
internet but somehow i was not able to connect to default
ftp.de.debian.org through "apt-get update", and to change source one
must edit /etc/apt/source.list which i am not able to edit
it as the file is only read-only.
Anyway i booted the system in linux resuce mode with FC3 rescue CD. I
said not to mount any file system(not even read only) when asked
during booting. Now first you need to activate the Volume Group, so
you need to do.
# lvm vgchange -ay
then to reduce the file system(in my case it is root file system of ext3
type) in the activated volume group, first you need to run,
"e2fsck -v -f LogicalVolumeWithFullPath" in my case it was,
# e2fsck -v -f /dev/VolGroup00/LogVol00
then resize it with
# resize2fs -p /dev/VolGroup00/LogVol00 6G
Resizes the ext3 file system in LogVol00 to 6GB.
Now after that When i check Logical Volumes with
# lvm lvdisplay
i get
--- Logical volume ---
LV Name /dev/VolGroup00/LogVol00
VG Name VolGroup00
LV UUID 6WyF9L-t4dJ-8HrR-NdTo-CoZh-NKvl-z6fidr
LV Write Access read/write
LV Status available
# open 1
LV Size 6.00 GB
Current LE 192
Segments 1
Allocation inherit
Read ahead sectors 0
Block device 253:0
--- Logical volume ---
LV Name /dev/VolGroup00/LogVol01
VG Name VolGroup00
LV UUID N3auhB-e9br-76Cw-Eqvw-c31w-mq3Y-T5QBp8
LV Write Access read/write
LV Status available
# open 1
LV Size 1.00 GB
Current LE 32
Segments 1
Allocation inherit
Read ahead sectors 0
Block device 253:1
So here i can see that LogVol00 is reduces to 6GB as i wanted. and
# lvm vgdisplay
shows,
VG Name VolGroup00
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 12
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 2
Open LV 2
Max PV 0
Cur PV 1
Act PV 1
VG Size 8.31 GB
PE Size 32.00 MB
Total PE 266
Alloc PE / Size 224 / 7.00 GB
Free PE / Size 42 / 1.31 GB
VG UUID cdEPbO-5o71-hUIa-szPC-FAra-E79P-cdbuTS
But it still shows it as 8.31GB which is like before, but it shows that
42 PEs are free.
But now the problem is how to claim those 42 PEs from this Volume Group
as i want to use that free space of this Volume Group to make
hda7(fat32)
which i can use(read/write)both in linux as well as in windows.
Do i have to do as Robin Suggested that,
>2. Move the swap volume back so it is adjacent to / (as it is swap, you
> could just run swapoff, delete the volume, and then recreate it.)
Can some one guide me step by step how to do it either from running FC3
itself or from rescue CD of FC3 or from Knoppix 3.7
> 3. Reduce the physical volume size
is there any command in lvm2 to do this, i tried
# lvm pvresize
but it said command not implemented yet. so how to do it?
Waiting for answers.
-ajeet.
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