BackupViaDDsnapshot

[drew@drewserv ~]$ sudo lvcreate -L10G -s -n tmpbkup /dev/vg-raid5/lv-raid5 
  Logical volume "tmpbkup" created

[drew@drewserv ~]$ sudo lvs
  LV        VG          Attr   LSize   Origin   Snap%  Move Log Copy%  Convert
  lv-backup vg-backup   -wi-ao 698.63g
  lv-raid5  vg-raid5    owi-ao 698.63g
  tmpbkup   vg-raid5    swi-ao  10.00g lv-raid5   0.13
  lv_home   vg_drewserv -wi-ao 178.44g
  lv_root   vg_drewserv -wi-ao  50.00g
  lv_swap   vg_drewserv -wi-ao   3.94g

[root@drewserv ~]#  date; dcfldd if=/dev/vg-raid5/tmpbkup of=/dev/vg-backup/lv-backup bs=4M; date
Sun Jul 24 05:29:04 MDT 2011
178688 blocks (714752Mb) written.
178850+0 records in
178850+0 records out
Sun Jul 24 12:14:20 MDT 2011

[root@drewserv ~]# tune2fs -U random /dev/vg-backup/lv-backup
tune2fs 1.41.14 (22-Dec-2010)

[root@drewserv etc]# mount /dev/vg-backup/lv-backup /mnt/backup

[root@drewserv backup]# ls -al /mnt/backup
total 33839996
drwxr-xr-x. 12 root root        4096 Jul 24 05:01 .
drwxr-xr-x.  5 root root        4096 Jul 23 19:05 ..
drwxr-xr-x.  5 user user        4096 Jul 24 00:06 backup

[root@drewserv ~]# lvremove /dev/vg-raid5/tmpbkup 
Do you really want to remove active logical volume tmpbkup? [y/n]: y
  Logical volume "tmpbkup" successfully removed

[drew@drewserv ~]$ sudo lvs
  LV        VG          Attr   LSize   Origin Snap%  Move Log Copy%  Convert
  lv-backup vg-backup   -wi-ao 698.63g                                      
  lv-raid5  vg-raid5    -wi-ao 698.63g                                      
  lv_home   vg_drewserv -wi-ao 178.44g                                      
  lv_root   vg_drewserv -wi-ao  50.00g                                      
  lv_swap   vg_drewserv -wi-ao   3.94g