Cannot use free space in filesystem

Question

I want to install a program but it says that there is not enough free disk space more than 11 GB although there is.

df -h shows:

Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_mach-lv_root
                       50G   39G   11G  79% /
tmpfs                 942M  540K  942M   1% /dev/shm
/dev/sda1             485M   55M  406M  12% /boot
/dev/mapper/vg_mach-lv_home
                      176G   27G  141G  17% /home

df -i shows:

Filesystem             Inodes  IUsed    IFree IUse% Mounted on
/dev/mapper/vg_resyslab-lv_root
                      3264000 583552  2680448   18% /
tmpfs                  220064     16   220048    1% /dev/shm
/dev/sda1              128016     46   127970    1% /boot
/dev/mapper/vg_resyslab-lv_home
                     11714560  12254 11702306    1% /home

Also the system monitor shows:

Command & Program output:

Answer 1

The information reported by your various tools are consistent. There is approximately 151Gb free on your disks, among which 141Gb for the /home directory and 11Gb for the rest of the system. What happens is that you program must install somewhere in /opt which is not under the same logical partition as /home where there is room but under the root partition when there is only 11Gb left.