Linux 扩展硬盘

[root@server12c /]# fdisk -l

Disk /dev/sda: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00016e57

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1          64      512000   83  Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2              64        2611    20458496   8e  Linux LVM

Disk /dev/sdb: 21.5 GB, 21474836480 bytes       #sdb为新加磁盘
255 heads, 63 sectors/track, 2610 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xc8e055ac
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虽然硬盘分区表中最多能存储四个分区，但我们实际使用时一般只分为两个分区，一个是主分区（Primary Partion）一个是扩展分区(extended partition)两种，主分区可以马上被使用但不能再分区，扩展分区必须再进行分区后才能使用，也就是说它必须还要进行二次分区。那么由扩充分区再分下去的是什么呢？它就是逻辑分区（Logical Partion），况且逻辑分区没有数量上限制。对习惯于使用Dos或Windows的朋友来说，有几个分区就有几个驱动器，并且每个分区都会获得一个字母标识符，然后就可以选用这个字母来指定在这个分区上的文件和目录，它们的文件结构都是独立的，非常好理解。但是初上手Red Hat Linux吗，可就有点恼人了。因为对Linux用户来说无论有几个分区，分给哪一目录使用，它归根结底就只有一个根目录，一个独立且唯一的文件结构。Red Hat Linux中每个分区都是用来组成整个文件系统的一部分，因为它采用了一种叫“挂载点”的处理方法，它的整个文件系统中包含了一整套的文件和目录，且将一个分区和一个目录联系起来。这时要载入的一个分区将使它的存储空间在一个目录下获得。

[root@server12c ~]# fdisk /dev/sdb

WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
         switch off the mode (command 'c') and change display units to
         sectors (command 'u').

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 action
   l   extend #扩展分区
   p   primary partition (1-4)#主分区
p
Partition number (1-4): 1 #分区号1
+2G
同上建立扩展分区

扩展分区建立好后就可以建逻辑分区
[root@server12c /]# fdisk /dev/sdb

WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
         switch off the mode (command 'c') and change display units to
         sectors (command 'u').

Command (m for help): n
Command action
   l   logical (5 or over)
   p   primary partition (1-4)
p
Partition number (1-4): 1
Partition 1 is already defined.  Delete it before re-adding it.

Command (m for help): ^[[A
[: unknown command
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
Command action
   l   logical (5 or over)
   p   primary partition (1-4)
p
Partition number (1-4): 2
First cylinder (786-2610, default 786):
Using default value 786
Last cylinder, +cylinders or +size{K,M,G} (786-2610, default 2610): +10G
Command (m for help): p

Disk /dev/sdb: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xc8e055ac

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1         262     2104483+  83  Linux
/dev/sdb2             786        2091    10490445   83  Linux
/dev/sdb4             263         785     4200997+   5  Extended
/dev/sdb5             263         785     4200966   83  Linux

Partition table entries are not in disk order

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

Calling ioctl() to re-read partition table.

格式化
[root@server12c /]# mkfs -t ext3 /dev/sdb4
mke2fs 1.43-WIP (20-Jun-2013)
mkfs.ext3: inode_size (128) * inodes_count (0) too big for a
    filesystem with 0 blocks, specify higher inode_ratio (-i)
or lower inode count (-N).

[root@server12c /]# mkfs -t ext3 /dev/sdb1
mke2fs 1.43-WIP (20-Jun-2013)
文件系统标签=
OS type: Linux
块大小=4096 (log=2)
分块大小=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
131648 inodes, 526120 blocks
26306 blocks (5.00%) reserved for the super user
第一个数据块=0
Maximum filesystem blocks=541065216
17 block groups
32768 blocks per group, 32768 fragments per group
7744 inodes per group
Superblock backups stored on blocks:
    32768, 98304, 163840, 229376, 294912

Allocating group tables: 完成                            
正在写入inode表: 完成                            
Creating journal (16384 blocks): 完成
Writing superblocks and filesystem accounting information: 完成
[root@server12c ~]# mkfs -t ext3 /dev/sdb2
mke2fs 1.43-WIP (20-Jun-2013)
文件系统标签=
OS type: Linux
块大小=4096 (log=2)
分块大小=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
655776 inodes, 2622611 blocks
131130 blocks (5.00%) reserved for the super user
第一个数据块=0
Maximum filesystem blocks=2688548864
81 block groups
32768 blocks per group, 32768 fragments per group
8096 inodes per group
Superblock backups stored on blocks:
    32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632

Allocating group tables: 完成                            
正在写入inode表: 完成                            
Creating journal (32768 blocks): 完成
Writing superblocks and filesystem accounting information: 完成

[root@server12c ~]# mkdir /data16
[root@server12c ~]# mount /dev/sdb2 /data16
[root@server12c ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_server12c-lv_root
                       18G   14G  3.0G  82% /
tmpfs                 1.9G     0  1.9G   0% /dev/shm
/dev/sda1             477M   84M  364M  19% /boot
/dev/sdb5             3.9G  8.2M  3.7G   1% /data15
/dev/sdb2             9.8G   23M  9.3G   1% /data16


新建目录并挂载
root@server12c ~]# mount /dev/sdb2 /data16
[root@server12c ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_server12c-lv_root
                       18G   14G  3.0G  82% /
tmpfs                 1.9G     0  1.9G   0% /dev/shm
/dev/sda1             477M   84M  364M  19% /boot
/dev/sdb5             3.9G  8.2M  3.7G   1% /data15
/dev/sdb2             9.8G   23M  9.3G   1% /data16


查看挂载是否成功

[root@server12c ~]# df -TH /data15/
Filesystem     Type  Size  Used Avail Use% Mounted on
/dev/sdb5      ext3  4.1G  8.6M  3.9G   1% /data15


防止重启手动挂载

[root@server12c ~]# vim /etc/fstab

/dev/sdb5 /data15 ext3 defaults 0 0

/dev/sdb2 /data16 ext3 defaults 0 0                            
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