树莓派挂载硬盘做nas，一段时间后硬盘突然变为只读，无法写入新文件

一、解决过程

1.卸载硬盘

 sudo umount /dev/sda2参数：-a, --all               unmount all filesystems-A, --all-targets       unmount all mountpoints for the given device in thecurrent namespace-c, --no-canonicalize   don't canonicalize paths-d, --detach-loop       if mounted loop device, also free this loop device--fake              dry run; skip the umount(2) syscall-f, --force             force unmount (in case of an unreachable NFS system)-i, --internal-only     don't call the umount.<type> helpers-n, --no-mtab           don't write to /etc/mtab-l, --lazy              detach the filesystem now, clean up things later-O, --test-opts <list>  limit the set of filesystems (use with -a)-R, --recursive         recursively unmount a target with all its children-r, --read-only         in case unmounting fails, try to remount read-only-t, --types <list>      limit the set of filesystem types-v, --verbose           say what is being done-q, --quiet             suppress 'not mounted' error messages-N, --namespace <ns>    perform umount in another namespace-h, --help              display this help-V, --version           display version

2.若此时出现 target is busy的提示，则说明有进程正在使用此硬盘；若无此提示则跳过此步骤

查看使用的进程：fuser -mv /home/pi/nas
杀死占用的进程：fuser -kv /home/pi/nas参数：
-a：显示命令行中指定的所有文件；
-k：杀死访问指定文件的所有进程；
-i：杀死进程前需要用户进行确认；
-l：列出所有已知信号名；
-m：指定一个被加载的文件系统或一个被加载的块设备；
-n：选择不同的名称空间；
-u：在每个进程后显示所属的用户名。

3.修复硬盘（可跳过）

sudo ntfsfix /dev/sda2参数：
-b, --clear-bad-sectors Clear the bad sector list
-d, --clear-dirty       Clear the volume dirty flag
-h, --help              Display this help
-n, --no-action         Do not write anything
-V, --version           Display version information

4.重新挂载硬盘

sudo mount -o rw /dev/sda2

5.通过df命令查看挂载情况，并验证硬盘支持读写的状态

df

6.通过mount命令查看硬盘读写状态

mount参数：
Options:-a, --all               mount all filesystems mentioned in fstab-c, --no-canonicalize   don't canonicalize paths-f, --fake              dry run; skip the mount(2) syscall-F, --fork              fork off for each device (use with -a)-T, --fstab <path>      alternative file to /etc/fstab-i, --internal-only     don't call the mount.<type> helpers-l, --show-labels       show also filesystem labels-n, --no-mtab           don't write to /etc/mtab--options-mode <mode>what to do with options loaded from fstab--options-source <source>mount options source--options-source-forceforce use of options from fstab/mtab-o, --options <list>    comma-separated list of mount options-O, --test-opts <list>  limit the set of filesystems (use with -a)-r, --read-only         mount the filesystem read-only (same as -o ro)-t, --types <list>      limit the set of filesystem types--source <src>      explicitly specifies source (path, label, uuid)--target <target>   explicitly specifies mountpoint--target-prefix <path>specifies path use for all mountpoints-v, --verbose           say what is being done-w, --rw, --read-write  mount the filesystem read-write (default)-N, --namespace <ns>    perform mount in another namespace-h, --help              display this help-V, --version           display version

通过/dev/sda2 on /home/pi/nas type fuseblk (rw,nosuid,nodev,noexec,relatime,user_id=   0,group_id=0,allow_other,blksize=4096)
可以看出，硬盘已经支持读写