mount命令应用和umount命令应用

记录：348

场景：在CentOS 7.9操作系统上，使用mount命令挂载镜像到指定目录、挂载磁盘到指定目录；使用umount命令卸载已挂载到指定目录的磁盘或者镜像。

版本：

操作系统：CentOS 7.9

1.mount命令应用

(1)把iso镜像挂载到指定目录

命令：mount -o loop /home/apps/software/CentOS-7-x86_64-Everything-2009.iso /mnt/local_iso/

解析：把CentOS-7-x86_64-Everything-2009.iso镜像挂载到指定的/mnt/local_iso/目录；loop是挂载loop设备类型。

(2)把磁盘挂载到指定目录

命令：mount /dev/sdb  /mnt/data

解析：/dev/sdb是磁盘在系统中的设备路径，系统新加的一个磁盘，需要创建文件系统和挂载到指定目录后，才能使用其存储空间。

(3)把磁盘分区挂载到指定目录

场景：磁盘/dev/sdb划分了两个分区，/dev/sdb1和/dev/sdb2，挂载时候，就直接使用分区挂载。

挂载磁盘分区1到目录：mount /dev/sdb1 /mnt/hz_data01

挂载磁盘分区2到目录：mount /dev/sdb2 /mnt/hz_data02

解析：/dev/sdb是磁盘在系统中的设备路径，/dev/sdb1和/dev/sdb2是磁盘在系统中两个分区的路径。

2.umount命令应用

(1)卸载已挂载到目录的iso镜像

卸载命令：umount /mnt/local_iso/

解析：卸载后，需要使用，必须重新挂载。

(2)卸载已挂载到目录的磁盘

卸载目录已挂载的磁盘：umount /dev/sdb

解析：执行umount后，目录就不可用了，也就无法使用磁盘空间了，如需使用，需重新挂载。

(3)卸载已挂载到目录的磁盘分区

卸载目录已挂载的磁盘分区sdb1：umount /dev/sdb1

卸载目录已挂载的磁盘分区sdb2：umount /dev/sdb2

解析：执行umount后，目录就不可用了，也就无法使用磁盘空间了，如需使用，需重新挂载。

3.命令帮助手册

(1)mount命令帮助手册

命令：mount --help

解析：查看mount支持的全部命令和选项，在实际工作中，查看这个手册应该是必备之选。

Usage:
 mount [-lhV]
 mount -a [options]
 mount [options] [--source] <source> | [--target] 
 mount [options] <source> 
 mount   []
 
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       alternative file to /etc/fstab
 -h, --help              display this help text and exit
 -i, --internal-only     don't call the mount.<type> helpers
 -l, --show-labels       lists all mounts with LABELs
 -n, --no-mtab           don't write to /etc/mtab
 -o, --options     comma-separated list of mount options
 -O, --test-opts   limit the set of filesystems (use with -a)
 -r, --read-only         mount the filesystem read-only (same as -o ro)
 -t, --types       limit the set of filesystem types
     --source       explicitly specifies source (path, label, uuid)
     --target    explicitly specifies mountpoint
 -v, --verbose           say what is being done
 -V, --version           display version information and exit
 -w, --rw, --read-write  mount the filesystem read-write (default)
 -h, --help     display this help and exit
 -V, --version  output version information and exit
Source:
 -L, --label      synonym for LABEL=
 -U, --uuid        synonym for UUID=
 LABEL=           specifies device by filesystem label
 UUID=             specifies device by filesystem UUID
 PARTLABEL=       specifies device by partition label
 PARTUUID=         specifies device by partition UUID
                 specifies device by path
              mountpoint for bind mounts (see --bind/rbind)
                   regular file for loopdev setup
Operations:
 -B, --bind              mount a subtree somewhere else (same as -o bind)
 -M, --move              move a subtree to some other place
 -R, --rbind             mount a subtree and all submounts somewhere else
 --make-shared           mark a subtree as shared
 --make-slave            mark a subtree as slave
 --make-private          mark a subtree as private
 --make-unbindable       mark a subtree as unbindable
 --make-rshared          recursively mark a whole subtree as shared
 --make-rslave           recursively mark a whole subtree as slave
 --make-rprivate         recursively mark a whole subtree as private
 --make-runbindable      recursively mark a whole subtree as unbindable
For more details see mount(8).
[root@hadoop200 ~]# 

(2)umount命令帮助手册

命令：umount --help

解析：查看umount支持的全部命令和选项，在实际工作中，查看这个手册应该是必备之选。

Usage:
 umount [-hV]
 umount -a [options]
 umount [options] <source> | 
 
Options:
 -a, --all               unmount all filesystems
 -A, --all-targets       unmount all mountpoins for the given device
                         in the current 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, and cleanup all later
 -O, --test-opts   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       limit the set of filesystem types
 -v, --verbose           say what is being done
 -h, --help     display this help and exit
 -V, --version  output version information and exit
For more details see umount(8).

以上，感谢。

2022年11月28日