Linux下添加新硬盘或去除硬盘

添加硬盘开机后
dmesg | grep sd
sda: sda1 sda2
sdb: unknown partition table
创建硬盘信息
fdisk /dev/sdb
Command (m for help): m
Command action
   a   toggle a bootable flag
   b   edit bsd disklabel
   c   toggle the dos compatibility flag
   d   delete a partition
   l   list known partition types
   m   print this menu
   n   add a new partition
   o   create a new empty DOS partition table
   p   print the partition table
   q   quit without saving changes
   s   create a new empty Sun disklabel
   t   change a partition’s system id
   u   change display/entry units
   v   verify the partition table
   w   write table to disk and exit
   x   extra functionality (experts only)

Command (m for help): n 添加分区
Command action
   e   extended
   p   primary partition (1-4)
p 添加主分区
Partition number (1-4): 1
First cylinder (1-2610, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-2610, default 2610):
Using default value 2610

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

格式化硬盘
[root@lmap ~]# mkfs -t ext3 /dev/sdb1
mke2fs 1.39 (29-May-2006)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
2621440 inodes, 5241198 blocks
262059 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=0
160 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

Writing inode tables: done                           
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 29 mounts or
180 days, whichever comes first.  Use tune2fs -c or -i to override.

创建mount目录
mkdir -p /mnt/CentOS01

mout到指定的目录
mount /dev/sdb1 /mnt/centos01

修改/etc/fstab文件，每次开机自动加载
vi /etc/fstab
/dev/sdb1               /mnt/centos01           ext3     defaults        1 1

查看
[root@lmap ~]# df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/mapper/VolGroup00-LogVol00
                      18156292   2574216  14644912  15% /
/dev/sda1               101086     18382     77485  20% /boot
tmpfs                   517552         0    517552   0% /dev/shm
/dev/sdb1             20635700    176200  19411264   1% /mnt/centos01

关于去除硬盘，修改/etc/fstab文件，删除相关内容

删除硬盘后如果不去掉/etc/fstab文件中的
/dev/sdb1               /mnt/centos01           ext3     defaults        1 1

重启后会出现
Give root password for maintenance
(or type Control-D to continue):

解决办法：
这是所有的文件系统是只读的，输入root密码后，使用这个命令
#mount -o remount,rw /
然后去掉/etc/fstab文件中的
/dev/sdb1               /mnt/centos01           ext3     defaults        1 1

reboot