R=( `df /srv/ftp/arch` ) ;
if [ ${R[10]} -lt 30000000 ] ; then 
    echo REMOVE 
fi

google:// man df

FREE_SPACE_TRESHOLD_ON_BACKUP_DISK=50               # in Gbytes

# Check how much place is available on backup disk, clear disk if empty space bellow the threshold
# During clearing we know how our backup directories called. Go from oldest to newest and delete oldest
# one by one until becomes empty space
function clear_backup_disk()
{
oldest=365 # in days
((FREE_SPACE_TRESHOLD_ON_BACKUP_DISK*=1024*1024)) # df command gives back free blocks in 1k, because of this dont multiple on 1024

    echo "Searching for $FREE_SPACE_TRESHOLD_ON_BACKUP_DISK empty Kbytes"


    # Go througth all files in mounted and delete them until enougth place will be allocated
    while [ $oldest -gt 1 ]
    do
        free_space_on_disk=`df $BACKUP_MOUNT | grep $mounted_disk | awk '{print $4}'`
        echo "oldest=$oldest free_space_on_disk=$free_space_on_disk"

        if [ $free_space_on_disk -lt $FREE_SPACE_TRESHOLD_ON_BACKUP_DISK ]
         then
              DIR_TO_DEL=$BACKUP_MOUNT/$(date '+20%y%m%d' -d "-$oldest days")"_Server"
              if [ -d $DIR_TO_DEL ]; then
                echo "* Found dir to delete $DIR_TO_DEL"
                rm -rf $DIR_TO_DEL
              fi
              ((oldest-=1))
        else
            echo "Got free space"
            break
        fi
    done
}