How to remove a PV from an LVM VG?
I think that my old disk is dying and I want to get the data off of it
before that happens. I just had the system drop out of X-windows and
lock up completely.
The screen was blank, except for three lines at the top:
[120497,729655] nouveau 0000:01:00.0: Setting dpms mode 3 on vga encoder
(output 0)
[120497,749909] nouveau 0000:01:00.0: Setting dpms mode 0 on vga encoder
(output 0)
[120497,749915] nouveau 0000:01:00.0: Output VGA-1 is running on CRTC 0
using Output A
This is the second time that this has happened. I was not home the
first time and I found it like that when I got home. I rebooted and
everything seemed OK.
This time, on rebooting I was dropped into single user mode. Apparently
the system had mounted my OLD / partition from the old drive instead of
the new partition on the new drive (neither of these partitions are in
the lvm group, they are physical partitions). I reran lilo and the
correct partition is being mounted as /, but I don't trust the old disk
any more. The old disk is a 40GB drive. I have previously installed a
1TB drive and have added it to the VG. I just need to make sure that I
do everything in the correct order so that I don't lose my data.
The old drive is /dev/sda and there are two PVs on the disk /dev/sda3
and /dev/sda4, both are in vg1
The new drive is /dev/sdc and it has only 1 LVM PV and that is /dev/sdc4
$ sudo pvdisplay
--- Physical volume ---
PV Name /dev/sda3
VG Name vg1
PV Size 17.24 GiB / not usable 1.38 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 4414
Free PE 0
Allocated PE 4414
PV UUID y0A9w2-Es63-ju5z-bSV0-JSbU-AdMj-j2U58I
--- Physical volume ---
PV Name /dev/sda4
VG Name vg1
PV Size 19.47 GiB / not usable 4.05 MiB
Allocatable yes (but full)
PE Size 4.00 MiB
Total PE 4984
Free PE 0
Allocated PE 4984
PV UUID hYLZpk-8lWT-Kna5-JwbV-3NpP-f3wP-zvKD63
--- Physical volume ---
PV Name /dev/sdc4
VG Name vg1
PV Size 928.56 GiB / not usable 1.83 MiB
Allocatable yes
PE Size 4.00 MiB
Total PE 237710
Free PE 224910
Allocated PE 12800
PV UUID N30XAD-155f-fRdA-0tch-dLU2-WMxP-z8jLCx
Is this the correct method to preserve my data:
pvmove /dev/sda3 /dev/sdc4
wait for it to finish
pvmove /dev/sda4 /dev/sdc4
once that has finished
vgreduce vg1 /dev/sda3
vgreduce vg1 /dev/sda4
pvremove /dev/sda3
pvremove /dev/sda4
I really need to know that this is the correct procedure and get this
done as quickly as possible. I don't want to lose data.
Marc Shapiro
Reply to: