dumpe2fs -h /dev/sda1 报错： 

dumpe2fs: Bad magic number in super-block while trying to open /dev/sda1 Couldn't find valid filesystem superblock. 

 mount -o remount,acl / 报错 mount: / not mounted or bad option       In some cases useful info is found in syslog - try       dmesg | tail or so. 

不晓得怎么回事呀老师？df信息如下

Filesystem              1K-blocks    Used Available Use% Mounted on

/dev/mapper/centos-root   6486016 4098144   2387872  64% /

devtmpfs                   497452       0    497452   0% /dev

tmpfs                      508116       0    508116   0% /dev/shm

tmpfs                      508116    6712    501404   2% /run

tmpfs                      508116       0    508116   0% /sys/fs/cgroup

/dev/sda1                 1038336  155940    882396  16% /boot

tmpfs                      101624       0    101624   0% /run/user/0