linux 挂载磁盘

挂在磁盘操作（还有一个300G的盘没显示出来）：

[root@iZgo67bo9s3uaijzqrgbaxZ ori]# df -h 
Filesystem            Size  Used Avail Use% Mounted on
/dev/hda1              39G   12G   26G  32% /
tmpfs                 4.0G     0  4.0G   0% /dev/shm

[root@iZgo67bo9s3uaijzqrgbaxZ backup]# fdisk -l    //查找未挂载的磁盘信息 
 
Disk /dev/hda: 42.9 GB, 42949672960 bytes
224 heads, 56 sectors/track, 6687 cylinders
Units = cylinders of 12544 * 512 = 6422528 bytes
 
Device Boot      Start         End      Blocks   Id  System
/dev/hda1   *           1        6688    41940992   83  Linux
Partition 1 does not end on cylinder boundary.
 
 Disk /dev/xvdb: 322.1 GB, 322122547200 bytes 
224 heads, 56 sectors/track, 50155 cylinders
Units = cylinders of 12544 * 512 = 6422528 bytes
 
Disk /dev/xvdb doesn't contain a valid partition table

[root@iZgo67bo9s3uaijzqrgbaxZ opt]#mkfs -t ext4 /dev/xvdb      //格式化未挂载的磁盘，使用ext4格式 
mke2fs 1.39 (29-May-2006)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
39321600 inodes, 78643200 blocks
3932160 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
2400 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872, 71663616
 
Writing inode tables: done                           
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
 
This filesystem will be automatically checked every 31 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.

[root@iZgo67bo9s3uaijzqrgbaxZ sdb]#mount /dev/xvdb /home    //将磁盘挂载到创建的目录上

实现自动挂载  vi /etc/fstab    添加  /dev/xvdb /home ext4 defaults 0 0

[root@iZgo67bo9s3uaijzqrgbaxZ sdb]# df -h        
Filesystem            Size  Used Avail Use% Mounted on
/dev/hda1              39G   12G   26G  32% /
tmpfs                 4.0G     0  4.0G   0% /dev/shm
 /dev/xvdb             296G  191M  281G   1% /mnt/sdb

[root@iZgo67bo9s3uaijzqrgbaxZ sdb]# mount -l     //显示挂载信息   

[root@iZgo67bo9s3uaijzqrgbaxZ sdb]# mount /home     //卸载挂载，卸载时需要先停掉运行在挂载磁盘上的应用