想umount一个不用的磁盘，结果提示：

[root@qttc mydata]# umount /mydata     
umount: /mydata: device is busy.
        (In some cases useful info about processes that use
         the device is found by lsof(8) or fuser(1))

 

于是只好用fuser命令来查看磁盘占用情况：

[root@qttc mydata]# fuser -m -v /mydata
                     USER        PID ACCESS COMMAND
/mydata:             root      16016 ..c.. bash
                     root      25011 ..c.. bash

第一行就是占用的，可以用kill命令来杀掉这个进程

[root@qttc mydata]# kill -9 16016

再此umount成功

[root@qttc ~]# umount /mydata

fuser具体参数，以及更多用法可以--help来看

[root@qttc /]# fuser --help
No process specification given
Usage: fuser [ -a | -s | -c ] [ -n SPACE ] [ -SIGNAL ] [ -kimuv ] NAME...
             [ - ] [ -n SPACE ] [ -SIGNAL ] [ -kimuv ] NAME...
       fuser -l
       fuser -V
Show which processes use the named files, sockets, or filesystems.

    -a        display unused files too
    -c        mounted FS
    -f        silently ignored (for POSIX compatibility)
    -i        ask before killing (ignored without -k)
    -k        kill processes accessing the named file
    -l        list available signal names
    -m        show all processes using the named filesystems
    -n SPACE  search in this name space (file, udp, or tcp)
    -s        silent operation
    -SIGNAL   send this signal instead of SIGKILL
    -u        display user IDs
    -v        verbose output
    -V        display version information
    -4        search IPv4 sockets only
    -6        search IPv6 sockets only
    -         reset options

  udp/tcp names: [local_port][,[rmt_host][,[rmt_port]]]