Hello
You are right the data are mounted in /media and the OS is less than 2GB
So I will use CloneZilla so as to backup the system before to upgrade
thks a lot for your solution,
bruno
df -h
/dev/mapper/omv-root 322M 163M 143M 54% /
tmpfs 3,8G 12K 3,8G 1% /lib/init/rw
udev 3,8G 172K 3,8G 1% /dev
tmpfs 3,8G 0 3,8G 0% /dev/shm
/dev/mapper/omv-tmp 349M 11M 321M 4% /tmp
/dev/mapper/omv-usr 7,4G 1,1G 6,0G 15% /usr
/dev/mapper/omv-var 2,8G 544M 2,1G 21% /var
/dev/sda2 237M 18M 207M 8% /boot
/dev/mapper/omv-nebula
1,5T 488G 952G 34% /media/f2ded637-9026-439a-8ddf-3e4a2cff0cbb
/dev/mapper/omv-mife 497G 117G 381G 24% /media/d797e57d-6b34-4032-9b41-3cccc5375f03
mount
/dev/mapper/omv-root on / type ext4 (rw,errors=remount-ro)
tmpfs on /lib/init/rw type tmpfs (rw,nosuid,mode=0755)
proc on /proc type proc (rw,noexec,nosuid,nodev)
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
udev on /dev type tmpfs (rw,mode=0755)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=620)
/dev/mapper/omv-tmp on /tmp type ext4 (rw)
/dev/mapper/omv-usr on /usr type ext4 (rw)
/dev/mapper/omv-var on /var type ext4 (rw)
/dev/sda2 on /boot type ext2 (rw)
/dev/mapper/omv-nebula on /media/f2ded637-9026-439a-8ddf-3e4a2cff0cbb type ext4 (rw,noexec,_netdev,acl,user_xattr,usrjquota=aquota.user,grpjquota=aquota.group,jqfmt=vfsv0)
/dev/mapper/omv-mife on /media/d797e57d-6b34-4032-9b41-3cccc5375f03 type xfs (rw,noexec,_netdev,usrquota,grpquota)
/media/f2ded637-9026-439a-8ddf-3e4a2cff0cbb/nebula on /export/nebula type none (rw,bind)
rpc_pipefs on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
nfsd on /proc/fs/nfsd type nfsd (rw)
