title: upgrade from Centos 6.7 to 7 without compromise the data in a LVM
body: <p>7 Server with 4 Discs and I have this configuration:</p>
  
  <ul>
  <li>"/" In a LVM (Physical disk 1)</li>
  <li>"/data" In LVM (Physical disk 1 + fake raid 0 of disks 2 and 3)</li>
  <li>"/data1" Ext4 (Physical disk 4)</li>
  </ul>
  
  <p>The server is a supermicro (motherboard model X8DTL) with 8gb of ram.</p>
  
  <p>I need to upgrade to centos 7 because the dependencies in the newer software are only in this distro but I have afraid of fuck UP With the data in "/data"</p>
  
  <p>How I can upgrade safely without screw with "/data"?</p>
  
  <p>PS:
  I can't make a backup, the information is more than 5TB.</p>
  
  <p>"/data" and "/data1" there are only standalone files (Text, spreadsheet files, multimedia files). The programs and associations are only in "/"</p>
  
  <p>Edit:
  Here it is how the disks are arranged:</p>
  
  <pre><code># lsblk -o NAME,FSTYPE,SIZE,MOUNTPOINT,LABEL
  NAME                               FSTYPE              SIZE MOUNTPOINT LABEL
  sda                                linux_raid_member 931,5G            GLaDOS:0
  └─md0                              LVM2_member         1,8T
    └─vg_glados_media-lv_data (dm-3) ext4                3,6T /data
  sdc                                linux_raid_member 931,5G            GLaDOS:0
  └─md0                              LVM2_member         1,8T
    └─vg_glados_media-lv_data (dm-3) ext4                3,6T /data
  sdb                                                    1,8T
  ├─sdb1                             ext4                500M /boot
  ├─sdb2                             LVM2_member        97,7G
  │ ├─vg_glados-lv_root (dm-0)       ext4                 50G /
  │ ├─vg_glados-lv_swap (dm-1)       swap                7,8G [SWAP]
  │ └─vg_glados-lv_home (dm-2)       ext4               39,9G /home
  └─sdb3                             LVM2_member         1,7T
    └─vg_glados_media-lv_data (dm-3) ext4                3,6T /data
  sdd                                                  931,5G
  └─sdd1                             ext4              931,5G /data1     /data1
  sr0                                                   1024M
  # df -H
  Filesystem            Size  Used Avail Use% Mounted on
  /dev/mapper/vg_glados-lv_root
                         53G   44G  6,6G  87% /
  tmpfs                 4,2G   78k  4,2G   1% /dev/shm
  /dev/sdb1             500M  132M  342M  28% /boot
  /dev/mapper/vg_glados_media-lv_data
                        3,9T  3,7T   28G 100% /data
  /dev/mapper/vg_glados-lv_home
                         42G  862M   39G   3% /home
  /dev/sdd1             985G  359G  576G  39% /data1
  </code></pre>