RHEL6-20-LOGICAL VOLUME MANAGER (LVM)-7

RHEL6-20-LOGICAL VOLUME MANAGER (LVM)-7

LVM OPERATIONS:

IMPORT & DEPORT OF VOLUME GROUP (VG):

LVM CONFIGURATION BACKUP & RESTORE:

How to do vgexport in linux?

How to do vgimport in linux?

How to move a volume group to another server in linux?

How to take backup of volume group (VG)?

What is LVM metadata?

How to restore volume group (VG)?

How to restore Logical volume group (LV) from VG backup?

Discuss various scenarios with volume group restore.

IMPORT & DEPORT OF VOLUME GROUP (VG):

Sometimes we might need that VG’s should be inaccessible. 

vgexport and vgimport is not necessary to move disk drives from one server to another. It is an administrative policy tool to prevent access to volumes in the time it takes to move them.

1^st, unmount the mounted FS’s under vg which need to move.

Here I want to move VG “vg01” having 2 LV’s mounted.

[root@rhel6-client1 ~]# df -kh

Filesystem            Size  Used Avail Use% Mounted on

/dev/sda6              15G  6.3G  7.4G  46% /

tmpfs                 937M   76K  937M   1% /dev/shm

/dev/sda1             485M   37M  423M   8% /boot

/dev/sda3            1008M   34M  924M   4% /home

/dev/sda2             2.9G   69M  2.7G   3% /opt

/dev/mapper/vg02-testlv01Fvg02

                      291M   11M  266M   4% /testlv01Fvg02

/dev/mapper/vg02-testlv02Fvg02

                      388M   11M  358M   3% /testlv02Fvg02

/dev/mapper/vg01-lv01Fvg01

                      485M   11M  449M   3% /lv01Fvg01

/dev/mapper/vg01-lv02Fvg01

                      291M   11M  266M   4% /lv02Fvg01

[root@rhel6-client1 ~]# umount /lv01Fvg01

[root@rhel6-client1 ~]# umount /lv02Fvg01

2^nd, Deactivate the VG.

[root@rhel6-client1 ~]# vgchange -a n vg01

  0 logical volume(s) in volume group "vg01" now active

[root@rhel6-client1 ~]# vgexport vg01

  Volume group "vg01" successfully exported

This prevents it from being accessed by the system from which we are removing it.

[root@rhel6-client1 ~]# pvs

  PV         VG   Fmt  Attr PSize    PFree

  /dev/sdd2  vg01 lvm2 ax-  1020.00m 220.00m

  /dev/sdd5  vg02 lvm2 a--     2.00g   1.31g

Look at the extra “x” in o/p. it means VG is exported.

[root@rhel6-client1 ~]# vgdisplay vg01

  Volume group vg01 is exported ççç

  --- Volume group ---

  VG Name               vg01

  System ID

  Format                lvm2

  Metadata Areas        1

  Metadata Sequence No  11

  VG Access             read/write

  VG Status             exported/resizable ççç

  MAX LV                0

  Cur LV                2

  Open LV               0

  Max PV                0

  Cur PV                1

  Act PV                1

  VG Size               1020.00 MiB

  PE Size               4.00 MiB

  Total PE              255

  Alloc PE / Size       200 / 800.00 MiB

  Free  PE / Size       55 / 220.00 MiB

  VG UUID               OK0vD5-GHIm-OQ6T-VyOX-vAtI-Dovk-asEiQ0

Now we need to export this VG on another system. My LVM Lab is based on internal disks, there is no external storage configured. Hence I cannot show. But here the steps.

3^rd, we need to do the “pvscan” on another system.

It will show us something like,

# pvscan

pvscan -- reading all physical volumes (this may take a while...)

pvscan -- inactive PV "/dev/sdb1"  is in EXPORTED VG "applv" [2.00 GiB / 1.31 GiB free]

pvscan -- inactive PV "/dev/sdb2"  is in EXPORTED VG "applv" [1020.00 MiB / 220.00 MiB free]

pvscan -- Total: 2 [2.99 GiB] / in use: 2 [2.99 GiB] / in no VG: 0 [0   ]

check all exported lv’s are showing on other system.

4^th, we need to import VG on that system.

[root@rhel6-client1 ~]# vgimport vg01

  Volume group "vg01" successfully imported

[root@rhel6-client1 ~]# vgdisplay vg01

  --- Volume group ---

  VG Name               vg01

  System ID

  Format                lvm2

  Metadata Areas        1

  Metadata Sequence No  12

  VG Access             read/write

  VG Status             resizable ççç

  MAX LV                0

  Cur LV                2

  Open LV               0

  Max PV                0

  Cur PV                1

  Act PV                1

  VG Size               1020.00 MiB

  PE Size               4.00 MiB

  Total PE              255

  Alloc PE / Size       200 / 800.00 MiB

  Free  PE / Size       55 / 220.00 MiB

  VG UUID               OK0vD5-GHIm-OQ6T-VyOX-vAtI-Dovk-asEiQ0

5^th, we need to activate the VG.

[root@rhel6-client1 ~]# vgchange -a y vg01

  2 logical volume(s) in volume group "vg01" now active

6^th, mount the FS.

[root@rhel6-client1 ~]# mount /dev/vg01/lv01Fvg01 /lv01Fvg01

[root@rhel6-client1 ~]# mount /dev/vg01/lv02Fvg01 /lv02Fvg01

[root@rhel6-client1 ~]# df -kh

Filesystem            Size  Used Avail Use% Mounted on

/dev/sda6              15G  6.3G  7.4G  46% /

tmpfs                 937M   76K  937M   1% /dev/shm

/dev/sda1             485M   37M  423M   8% /boot

/dev/sda3            1008M   34M  924M   4% /home

/dev/sda2             2.9G   69M  2.7G   3% /opt

/dev/mapper/vg02-testlv01Fvg02

                      291M   11M  266M   4% /testlv01Fvg02

/dev/mapper/vg02-testlv02Fvg02

                      388M   11M  358M   3% /testlv02Fvg02

/dev/mapper/vg01-lv01Fvg01

                      485M   11M  449M   3% /lv01Fvg01

/dev/mapper/vg01-lv02Fvg01

                      291M   11M  266M   4% /lv02Fvg01

LVM CONFIGURATION BACKUP & RESTORE:

What does it mean to lvm config backup? Is it going to take entire data backup?

Simply … NO

It is saying itself that I am config backup.

What is config backup?

It might be something which keep track of all PV/Vg/LV.

What it is called?

LVM Metadat.

The LVM metadata contains the configuration details of the LVM volume groups on your system. By default, an identical copy of the metadata is maintained in every metadata area in every physical volume within the volume group. LVM metadata is small and stored as ASCII.

Currently LVM allows us to store 0, 1 or 2 identical copies of its metadata on each physical volume. The default is 1 copy.

The first copy is stored at the start of the device, shortly after the label. If there is a second copy, it is placed at the end of the device. If you accidentally overwrite the area at the beginning of your disk by writing to a different disk than you intend, a second copy of the metadata at the end of the device will allow you to recover the metadata.

By default, the LVM label is placed in the second 512-byte sector. An LVM label provides correct identification and device ordering for a physical device, since devices can come up in any order when the system is booted. An LVM label remains persistent across reboots and throughout a cluster.

The LVM label identifies the device as an LVM physical volume. It contains a random unique identifier (the UUID) for the physical volume. It also stores the size of the block device in bytes, and it records where the LVM metadata will be stored on the device.

FIRST SECTOR

SECOND SECTOR WITH LVM LABEL

LVM METADATA

USER SPACE

Reference & Good Read:

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/5/html/Logical_Volume_Manager_Administration/lvm_metadata.html

https://www.centos.org/docs/5/html/Cluster_Logical_Volume_Manager/physical_volumes.html

https://www.centos.org/docs/5/html/Cluster_Logical_Volume_Manager/mdatarecover.html

By default backup is created under

/etc/lvm/backup/

[root@rhel6-client1 ~]# ls -ltr /etc/lvm/

total 52

-rw-r--r--. 1 root root 37554 Jan 23  2013 lvm.conf

drwx------. 2 root root  4096 Jan 23  2013 cache

drwx------. 2 root root  4096 Apr  2 18:59 archive

drwx------. 2 root root  4096 Apr  2 18:59 backup

[root@rhel6-client1 ~]# ls -ltr /etc/lvm/backup/

total 8

-rw-------. 1 root root 1714 Apr  1 15:37 vg02

-rw-------. 1 root root 1698 Apr  2 18:59 vg01

It is also interesting to look into

[root@rhel6-client1 ~]# ls -ltr /etc/lvm/archive/

total 300

-rw-------. 1 root root 1119 Mar 28 16:14 vg01_00000-1910704701.vg

-rw-------. 1 root root  882 Mar 28 18:37 testvg01_00000-1950708648.vg

-rw-------. 1 root root  873 Mar 28 18:37 testvg01_00001-682674067.vg

-rw-------. 1 root root 1367 Mar 28 18:47 myvg01_00000-2043074889.vg

-rw-------. 1 root root 1355 Mar 28 18:47 myvg01_00001-265674543.vg

-rw-------. 1 root root 2921 Mar 29 11:57 vg01_00005-1147184297.vg

-rw-------. 1 root root 2126 Apr  1 13:48 vg02_00004-1487957776.vg

-rw-------. 1 root root 3180 Apr  1 13:48 vg-test01_00000-642616270.vg

-rw-------. 1 root root 3626 Apr  1 14:42 vg-test01_00001-325208930.vg

-rw-------. 1 root root 6115 Apr  1 14:42 myvg01_00005-266411389.vg

-rw-------. 1 root root 3477 Apr  1 14:47 vg02_00008-2097263409.vg

-rw-------. 1 root root 3073 Apr  1 14:47 vg02_00009-202753883.vg

-rw-------. 1 root root 3705 Apr  1 14:48 vg-test01_00002-673949358.vg

-rw-------. 1 root root 3303 Apr  1 14:49 vg-test01_00003-1627573653.vg

-rw-------. 1 root root 6178 Apr  1 14:50 myvg01_00006-296488171.vg

-rw-------. 1 root root 5776 Apr  1 14:50 myvg01_00007-1539032331.vg

-rw-------. 1 root root 4047 Apr  1 14:50 myvg01_00008-2029974350.vg

-rw-------. 1 root root 1832 Apr  1 14:50 myvg01_00009-1009471958.vg

-rw-------. 1 root root 1353 Apr  1 14:53 myvg01_00010-1399856037.vg

-rw-------. 1 root root 1824 Apr  1 14:53 vg-test01_00006-1506723838.vg

-rw-------. 1 root root 1349 Apr  1 14:53 vg02_00013-1516538053.vg

===============O/P MODIFIED==============================

I can see all deleted as well as active vg’s under archive.

So actually what does it contain…?

Here the automatic archives go after a volume group change

How many days it will be available?

Depends upon the parameters set in /etc/lvm/lvm.conf

[root@rhel6-client1 ~]# grep retain_min /etc/lvm/lvm.conf

    retain_min = 10

[root@rhel6-client1 ~]# grep retain_days /etc/lvm/lvm.conf

    retain_days = 30

What if I want to take it manually?

[root@rhel6-client1 ~]# vgcfgbackup

  Volume group "vg02" successfully backed up.

  Volume group "vg01" successfully backed up.

But where…?

Overwritten on

[root@rhel6-client1 ~]# ls -ltr /etc/lvm/backup/

total 8

-rw-------. 1 root root 1702 Apr  2 19:21 vg02

-rw-------. 1 root root 1696 Apr  2 19:21 vg01

I want to save it at another place.

[root@rhel6-client1 ~]# vgcfgbackup -f /tmp/vg01 vg01

  Volume group "vg01" successfully backed up.

[root@rhel6-client1 ~]# vgcfgbackup -f /tmp/vg02 vg02

  Volume group "vg02" successfully backed up.

[root@rhel6-client1 ~]# ls -l /tmp/vg*

-rw-------. 1 root root 1686 Apr  2 19:24 /tmp/vg01

-rw-------. 1 root root 1692 Apr  2 19:24 /tmp/vg02

Can we test it…?

Sure…Why not.

Scenario-1 = Destroying only LV.

[root@rhel6-client1 ~]# lvs

  LV            VG   Attr      LSize   Pool Origin Data%  Move Log Cpy%Sync Convert

  lv01Fvg01     vg01 -wi-ao--- 500.00m

  lv02Fvg01     vg01 -wi-ao--- 300.00m

  testlv01Fvg02 vg02 -wi-ao--- 300.00m

  testlv02Fvg02 vg02 -wi-ao--- 400.00m

[root@rhel6-client1 ~]# cd /lv01Fvg01

[root@rhel6-client1 lv01Fvg01]# touch 1 2 3

[root@rhel6-client1 lv01Fvg01]# vi 1

[root@rhel6-client1 lv01Fvg01]# ls -l /lv01Fvg01

total 16

-rw-r--r--. 1 root root    57 Apr  3 15:17 1

-rw-r--r--. 1 root root     0 Apr  3 15:16 2

-rw-r--r--. 1 root root     0 Apr  3 15:16 3

drwx------. 2 root root 12288 Apr  1 14:59 lost+found

[root@rhel6-client1 lv01Fvg01]# cat 1

nfve/wnv/elwbnlewnbldfnmb.m b,cv c, n,nk ngklgnb xnb sn

I want to remove /lv01Fvg01, I had created 3 files under that.

Now I am going to remove /lv01Fvg01,

[root@rhel6-client1 lv01Fvg01]# cd

[root@rhel6-client1 ~]# umount /lv01Fvg01

[root@rhel6-client1 ~]# lvremove /dev/vg01/lv01Fvg01

Do you really want to remove active logical volume lv01Fvg01? [y/n]: y

  Logical volume "lv01Fvg01" successfully removed

 [root@rhel6-client1 ~]# lvs

  LV            VG   Attr      LSize   Pool Origin Data%  Move Log Cpy%Sync Convert

  lv02Fvg01     vg01 -wi-ao--- 300.00m

  testlv01Fvg02 vg02 -wi-ao--- 300.00m

  testlv02Fvg02 vg02 -wi-ao--- 400.00m

[root@rhel6-client1 ~]# vgcfgrestore -f /tmp/vg01 vg01

  Restored volume group vg01

[root@rhel6-client1 ~]# mount /dev/vg01/lv01Fvg01 /lv01Fvg01

mount: you must specify the filesystem type

[root@rhel6-client1 ~]# lvdisplay /dev/vg01/lv01Fvg01

  --- Logical volume ---

  LV Path                /dev/vg01/lv01Fvg01

  LV Name                lv01Fvg01

  VG Name                vg01

  LV UUID                Qp3U0l-p3hB-3vgK-uV11-G9TI-KVz6-UszwZy

  LV Write Access        read/write

  LV Creation host, time rhel6-client1, 2017-04-01 14:56:18 +0530

  LV Status              NOT available ççç

  LV Size                500.00 MiB

  Current LE             125

  Segments               1

  Allocation             inherit

  Read ahead sectors     auto

[root@rhel6-client1 ~]# lvchange -ay /dev/vg01/lv01Fvg01

[root@rhel6-client1 ~]# lvdisplay /dev/vg01/lv01Fvg01

  --- Logical volume ---

  LV Path                /dev/vg01/lv01Fvg01

  LV Name                lv01Fvg01

  VG Name                vg01

  LV UUID                Qp3U0l-p3hB-3vgK-uV11-G9TI-KVz6-UszwZy

  LV Write Access        read/write

  LV Creation host, time rhel6-client1, 2017-04-01 14:56:18 +0530

  LV Status              available ççç

  # open                 0

  LV Size                500.00 MiB

  Current LE             125

  Segments               1

  Allocation             inherit

  Read ahead sectors     auto

  - currently set to     256

  Block device           253:0

[root@rhel6-client1 ~]# mount /dev/vg01/lv01Fvg01 /lv01Fvg01

[root@rhel6-client1 ~]# ls -l /lv01Fvg01

total 16

-rw-r--r--. 1 root root    57 Apr  3 15:17 1

-rw-r--r--. 1 root root     0 Apr  3 15:16 2

-rw-r--r--. 1 root root     0 Apr  3 15:16 3

drwx------. 2 root root 12288 Apr  1 14:59 lost+found

[root@rhel6-client1 ~]# cat /lv01Fvg01/1

nfve/wnv/elwbnlewnbldfnmb.m b,cv c, n,nk ngklgnb xnb sn

[root@rhel6-client1 ~]#

[root@rhel6-client1 ~]# vgs -o vg_name,vg_size,devices

  VG   VSize    Devices

  vg01 1020.00m /dev/sdd2(0)

  vg01 1020.00m /dev/sdd2(125)

  vg02    2.00g /dev/sdd5(0)

  vg02    2.00g /dev/sdd5(75)

Great……LV restored.

Let’s consider one more scenario for restoration.

Scenario-2 = Destroying all LV, VG & PV.

[root@rhel6-client1 ~]# umount /lv01Fvg01

[root@rhel6-client1 ~]# umount /lv02Fvg01

[root@rhel6-client1 ~]# vgremove vg01

Do you really want to remove volume group "vg01" containing 2 logical volumes? [y/n]: y

Do you really want to remove active logical volume lv01Fvg01? [y/n]: y

  Logical volume "lv01Fvg01" successfully removed

Do you really want to remove active logical volume lv02Fvg01? [y/n]: y

  Logical volume "lv02Fvg01" successfully removed

  Volume group "vg01" successfully removed

[root@rhel6-client1 ~]# pvremove /dev/sdd2

  Labels on physical volume "/dev/sdd2" successfully wiped

[root@rhel6-client1 ~]# vgcfgrestore -f /tmp/vg01 vg01

  Couldn't find device with uuid VJK3rn-O3ql-V6nG-WFx0-hF2n-VFcw-W6DryY.

  Cannot restore Volume Group vg01 with 1 PVs marked as missing.

  Restore failed.

All gone, means we must have PV intact.

I created PV-VG-LV again

[root@rhel6-client1 ~]# lvs

  LV            VG   Attr      LSize   Pool Origin Data%  Move Log Cpy%Sync Convert

  lv01Fvg01     vg01 -wi-a---- 300.00m

  lv02Fvg01     vg01 -wi-a---- 400.00m

  testlv01Fvg02 vg02 -wi-ao--- 300.00m

  testlv02Fvg02 vg02 -wi-ao--- 400.00m

[root@rhel6-client1 ~]# mount /dev/vg01/lv01Fvg01 /lv01Fvg01

[root@rhel6-client1 ~]# mount /dev/vg01/lv02Fvg01 /lv02Fvg01

[root@rhel6-client1 ~]# cd /lv01Fvg01

[root@rhel6-client1 lv01Fvg01]# touch aa bb cc dd

[root@rhel6-client1 lv01Fvg01]# vi aa

[root@rhel6-client1 lv01Fvg01]# cat aa

hi this is test test test test

Now consider one more scenario,

Scenario-3 = Destroying LV & VG.

[root@rhel6-client1 ~]# vgcfgbackup -f /tmp/vg01 vg01

  Volume group "vg01" successfully backed up.

[root@rhel6-client1 ~]# umount /lv01Fvg01

[root@rhel6-client1 ~]# umount /lv02Fvg01

[root@rhel6-client1 ~]# lvremove /dev/vg01/lv01Fvg01

Do you really want to remove active logical volume lv01Fvg01? [y/n]: y

  Logical volume "lv01Fvg01" successfully removed

[root@rhel6-client1 ~]# lvremove /dev/vg01/lv02Fvg01

Do you really want to remove active logical volume lv02Fvg01? [y/n]: y

  Logical volume "lv02Fvg01" successfully removed

[root@rhel6-client1 ~]# vgremove vg01

  Volume group "vg01" successfully removed

[root@rhel6-client1 ~]# vgcfgrestore -f /tmp/vg01 vg01

  Restored volume group vg01

[root@rhel6-client1 ~]# vgs

  VG   #PV #LV #SN Attr   VSize    VFree

  vg01   1   2   0 wz--n- 1020.00m 320.00m

  vg02   1   2   0 wz--n-    2.00g   1.31g

[root@rhel6-client1 ~]# lvs

  LV            VG   Attr      LSize   Pool Origin Data%  Move Log Cpy%Sync Convert

  lv01Fvg01     vg01 -wi------ 300.00m ççç (ao flag missing)

  lv02Fvg01     vg01 -wi------ 400.00m ççç (ao flag missing)

  testlv01Fvg02 vg02 -wi-ao--- 300.00m

  testlv02Fvg02 vg02 -wi-ao--- 400.00m

[root@rhel6-client1 ~]# lvchange -ay /dev/vg01/lv01Fvg01

[root@rhel6-client1 ~]# lvchange -ay /dev/vg01/lv02Fvg01

[root@rhel6-client1 ~]# lvs

  LV            VG   Attr      LSize   Pool Origin Data%  Move Log Cpy%Sync Convert

  lv01Fvg01     vg01 -wi-a---- 300.00m ççç (o flag missing)

  lv02Fvg01     vg01 -wi-a---- 400.00m ççç (o flag missing)

  testlv01Fvg02 vg02 -wi-ao--- 300.00m

  testlv02Fvg02 vg02 -wi-ao--- 400.00m

[root@rhel6-client1 ~]# mount /dev/vg01/lv01Fvg01 /lv01Fvg01

[root@rhel6-client1 ~]# mount /dev/vg01/lv02Fvg01 /lv02Fvg01

[root@rhel6-client1 ~]# lvs

  LV            VG   Attr      LSize   Pool Origin Data%  Move Log Cpy%Sync Convert

  lv01Fvg01     vg01 -wi-ao--- 300.00m

  lv02Fvg01     vg01 -wi-ao--- 400.00m

  testlv01Fvg02 vg02 -wi-ao--- 300.00m

  testlv02Fvg02 vg02 -wi-ao--- 400.00m

[root@rhel6-client1 ~]# ls -l /lv01Fvg01

total 17

-rw-r--r--. 1 root root    31 Apr  3 16:23 aa

-rw-r--r--. 1 root root     0 Apr  3 16:23 bb

-rw-r--r--. 1 root root     0 Apr  3 16:23 cc

-rw-r--r--. 1 root root     0 Apr  3 16:23 dd

drwx------. 2 root root 12288 Apr  3 16:23 lost+found

[root@rhel6-client1 ~]# cat /lv01Fvg01/aa

hi this is test test test test

Great, again restored

What happen if I create some LV and then try to restore…?

Scenario-4 = Destroying LV and create other LV on that VG, then restore.

[root@rhel6-client1 ~]# umount /lv01Fvg01

[root@rhel6-client1 ~]# umount /lv02Fvg01

[root@rhel6-client1 ~]# lvremove /dev/vg01/lv01Fvg01

Do you really want to remove active logical volume lv01Fvg01? [y/n]: y

  Logical volume "lv01Fvg01" successfully removed

[root@rhel6-client1 ~]# lvremove /dev/vg01/lv02Fvg01

Do you really want to remove active logical volume lv02Fvg01? [y/n]: y

  Logical volume "lv02Fvg01" successfully removed

 [root@rhel6-client1 ~]# lvcreate -L 450M -n testlv01 vg01

  Rounding up size to full physical extent 452.00 MiB

  Logical volume "testlv01" created

[root@rhel6-client1 ~]# lvs

  LV            VG   Attr      LSize   Pool Origin Data%  Move Log Cpy%Sync Convert

  testlv01      vg01 -wi-a---- 452.00m

  testlv01Fvg02 vg02 -wi-ao--- 300.00m

  testlv02Fvg02 vg02 -wi-ao--- 400.00m

[root@rhel6-client1 ~]# mkfs.ext4 /dev/vg01/testlv01

mke2fs 1.41.12 (17-May-2010)

Filesystem label=

OS type: Linux

Block size=1024 (log=0)

Fragment size=1024 (log=0)

Stride=0 blocks, Stripe width=0 blocks

115824 inodes, 462848 blocks

23142 blocks (5.00%) reserved for the super user

First data block=1

Maximum filesystem blocks=67633152

57 block groups

8192 blocks per group, 8192 fragments per group

2032 inodes per group

Superblock backups stored on blocks:

        8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409

Writing inode tables: done

Creating journal (8192 blocks): done

Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 29 mounts or

180 days, whichever comes first.  Use tune2fs -c or -i to override.

[root@rhel6-client1 ~]# mkdir /testlv01

[root@rhel6-client1 ~]# mount /dev/vg01/testlv01 /testlv01

[root@rhel6-client1 ~]# cd /testlv01

[root@rhel6-client1 testlv01]# touch f1 f2 f3

[root@rhel6-client1 testlv01]# ls -l

total 15

-rw-r--r--. 1 root root     0 Apr  3 16:46 f1

-rw-r--r--. 1 root root     0 Apr  3 16:46 f2

-rw-r--r--. 1 root root     0 Apr  3 16:46 f3

drwx------. 2 root root 12288 Apr  3 16:45 lost+found

[root@rhel6-client1 testlv01]# cd

[root@rhel6-client1 ~]# vgs;lvs

  VG   #PV #LV #SN Attr   VSize    VFree

  vg01   1   1   0 wz--n- 1020.00m 568.00m

  vg02   1   2   0 wz--n-    2.00g   1.31g

  LV            VG   Attr      LSize   Pool Origin Data%  Move Log Cpy%Sync Convert

  testlv01      vg01 -wi-ao--- 452.00m

  testlv01Fvg02 vg02 -wi-ao--- 300.00m

  testlv02Fvg02 vg02 -wi-ao--- 400.00m

[root@rhel6-client1 ~]# vgcfgrestore -f /tmp/vg01 vg01

  Restored volume group vg01

[root@rhel6-client1 ~]# vgs;lvs

  VG   #PV #LV #SN Attr   VSize    VFree

  vg01   1   2   0 wz--n- 1020.00m 320.00m

  vg02   1   2   0 wz--n-    2.00g   1.31g

  LV            VG   Attr      LSize   Pool Origin Data%  Move Log Cpy%Sync Convert

  lv01Fvg01     vg01 -wi------ 300.00m

  lv02Fvg01     vg01 -wi------ 400.00m

  testlv01Fvg02 vg02 -wi-ao--- 300.00m

  testlv02Fvg02 vg02 -wi-ao--- 400.00m

[root@rhel6-client1 ~]# lvchange -ay /dev/vg01/lv01Fvg01

[root@rhel6-client1 ~]# lvchange -ay /dev/vg01/lv02Fvg01

[root@rhel6-client1 ~]#

[root@rhel6-client1 ~]# mount /dev/vg01/lv01Fvg01 /lv01Fvg01

[root@rhel6-client1 ~]# mount /dev/vg01/lv02Fvg01 /lv02Fvg01

[root@rhel6-client1 ~]# ls -l /lv01Fvg01

total 17

-rw-r--r--. 1 root root    31 Apr  3 16:23 aa

-rw-r--r--. 1 root root     0 Apr  3 16:23 bb

-rw-r--r--. 1 root root     0 Apr  3 16:23 cc

-rw-r--r--. 1 root root     0 Apr  3 16:23 dd

drwx------. 2 root root 12288 Apr  3 16:23 lost+found

[root@rhel6-client1 ~]# cat /lv01Fvg01/aa

hi this is test test test test

Great, again restored.