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Clone an LVM based KVM based Virtual Machine ;-)

I recently opted to use a volume for my VM (instead of creating a file).

RHEVM01 is the "source" and RHUTIL01 is the destination.  I am also cloning from my vg_blackmesa to vg_apps.  One thing I would like to figure out is how to monitor the progress.


root@blackmesa ~]# lvdisplay /dev/mapper/vg_blackmesa-VM_RHEVM01
  --- Logical volume ---
  LV Path                /dev/vg_blackmesa/VM_RHEVM01
  LV Name                VM_RHEVM01
  VG Name                vg_blackmesa
  LV UUID                zx4BLV-Athf-Ymcd-ox4h-965J-uo30-Aey9dJ
  LV Write Access        read/write
  LV Creation host, time blackmesa.area51.private, 2012-06-22 00:12:02 -0500
  LV Status              available
  # open                 1
  LV Size                20.00 GiB
  Current LE             5120
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:6


[root@blackmesa ~]# vgs
  VG           #PV #LV #SN Attr   VSize   VFree  
  vg_apps        1   1   0 wz--n- 278.46g 153.46g
  vg_blackmesa   1   6   0 wz--n- 135.29g  43.29g


[root@blackmesa ~]# lvcreate -nVM_RHUTIL01 -L20g vg_apps
  Logical volume "VM_RHUTIL01" created


[root@blackmesa ~]# lvdisplay /dev/mapper/vg_apps-VM_RHUTIL01 
  --- Logical volume ---
  LV Path                /dev/vg_apps/VM_RHUTIL01
  LV Name                VM_RHUTIL01
  VG Name                vg_apps
  LV UUID                EM6eA5-Jcww-iugy-UfRn-GgJE-cvaC-P5i1Wd
  LV Write Access        read/write
  LV Creation host, time blackmesa.area51.private, 2012-06-22 19:14:04 -0500
  LV Status              available
  # open                 0
  LV Size                20.00 GiB
  Current LE             5120
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:7


-- During the copy, you can watch via iostat

[root@blackmesa ~]# ls -l /dev/mapper/vg_blackmesa-VM_RHEVM01 
lrwxrwxrwx. 1 root root 7 Jun 22 00:12 /dev/mapper/vg_blackmesa-VM_RHEVM01 -> ../dm-6
[root@blackmesa ~]# dd if=/dev/dm-6 of=^C
[root@blackmesa ~]# ls -l /dev/mapper/vg_apps-VM_RHUTIL01 
lrwxrwxrwx. 1 root root 7 Jun 22 19:14 /dev/mapper/vg_apps-VM_RHUTIL01 -> ../dm-7


[root@blackmesa ~]# dd if=/dev/dm-6 of=/dev/dm-7 bs=512K 
40960+0 records in
40960+0 records out
21474836480 bytes (21 GB) copied, 273.34 s, 78.6 MB/s
[root@blackmesa qemu]# cat RHEVM01.xml | sed 's/RHEVM01/RHUTIL01/g' > RHUTIL01.xml
[root@blackmesa qemu]# uuidgen 
bffa485a-70d3-4d58-80b2-bf1a56a81928
OR... use

[root@blackmesa ~]# dd if=/dev/vg_blackmesa/VM_RHEVM01 of=/dev/mapper/vg_apps-VM_RHUTIL01 bs=512K


[root@blackmesa qemu]#  vi RHUTIL01.xml
-- update 
    uuid
    Description (if present)
    name
    macaddress
[root@blackmesa qemu]# service libvirtd restart 
[root@blackmesa qemu]# virsh start RHUTIL01 && virsh start RHEVM01; 
[root@blackmesa qemu]# sudo virsh list --all
 Id    Name                           State
----------------------------------------------------
 1     CRWX01                         running
 2     RHNSAT01                       running
 3     WINPDC01                       running
 4     RHEVM01                        running
 5     RHUTIL01                       running


-- You will, of course, need to update your network configuration inside
   the cloned VM because of the new mac address.

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