其实Linux环境下挂载USB设备并不算复杂。

首先通过fdisk –l检查USB设备是否已经被系统识别：

[root@bjtest ~]# fdisk -l

Disk /dev/sda: 1197.7 GB, 1197759004672 bytes

255 heads, 63 sectors/track, 145619 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot      Start         End      Blocks   Id  System

/dev/sda1   *           1          13      104391   83  Linux

/dev/sda2              14        5235    41945715   83  Linux

/dev/sda3            5236       10457    41945715   83  Linux

/dev/sda4           10458      145619  1085688765    5  Extended

/dev/sda5           10458       13068    20972826   83  Linux

/dev/sda6           13069       14112     8385898+  82  Linux swap / Solaris

/dev/sda7           14113      145619  1056329946   83  Linux

Disk /dev/sdb: 60.0 GB, 60022480896 bytes

255 heads, 63 sectors/track, 7297 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot      Start         End      Blocks   Id  System

/dev/sdb1               2        3825    30716280    f  W95 Ext'd (LBA)

/dev/sdb2   *        3826        7297    27888840    c  W95 FAT32 (LBA)

/dev/sdb5               2        3825    30716248+   b  W95 FAT32

可以看到/dev/sdb就是USB盘，而且这个U盘花费了多个区，尝试通过MOUNT命令挂载U盘，对于fat16、fat32和ntfs在Linux系统中可以统一使用vfat来指定：

[root@bjtest ~]# mkdir /mnt/usb1 /mnt/usb2

[root@bjtest ~]# mount -t vfat /dev/sdb1 /mnt/usb1

mount: wrong fs type, bad option, bad superblock on /dev/sdb1,

missing codepage or other error

(aren't you trying to mount an extended partition,

instead of some logical partition inside?)

In some cases useful info is found in syslog - try

dmesg | tail  or so

[root@bjtest ~]# mount -t vfat /dev/sdb2 /mnt/usb1

[root@bjtest ~]# mount -t vfat /dev/sdb5 /mnt/usb2

[root@bjtest ~]# df -k

Filesystem           1K-blocks      Used Available Use% Mounted on

/dev/sda2             40631988  17589084  20945620  46% /

/dev/sda1               101086     15958     79909  17% /boot

/dev/sda7            1023246840 783797928 186632416  81% /data

tmpfs                  8209472   3989672   4219800  49% /dev/shm

/dev/sda3             40631988  13570856  24963848  36% /home

/dev/sda5             20315812    176352  19090820   1% /tmp

/dev/sdb2             27875200  19757344   8117856  71% /mnt/usb1

/dev/sdb5             30701232       176  30701056   1% /mnt/usb2

其中/dev/sdb1无法挂载，不过可以看到，/dev/sdb2和/dev/sdb5挂载后，两个文件系统总和就是60G，说明USB盘已经挂载成功。

卸载USB设备就更容易了，只需要执行umount /mnt/usb1和umount /mnt/usb2就可以了：

[root@bjtest /]# umount /mnt/usb1

[root@bjtest /]# umount /mnt/usb2