linux 新建挂载空闲磁盘空间
本人有块SCSI硬盘，安装Linux AS4 时没有分区，安装好了系统后想把这块空闲分区使用上，以下是详细的操作步骤
一、使用linux as4的硬件查看工具查看未使用的硬盘空间。
二、使用fdisk对空闲分区分区。
[root@guohuilinuxas31 root]# fdisk /dev/sda
The number of cylinders for this disk is set to 5221.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
(e.g., DOS FDISK, OS/2 FDISK)
Command (m for help): p
Disk /dev/sda: 42.9 GB, 42949672960 bytes
255 heads, 63 sectors/track, 5221 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 2356 18820147+ 83 Linux
/dev/sda3 2357 2610 2040255 82 Linux swap
Command (m for help): n
Command action
e extended
p primary partition (1-4)
e（这里我选的p,用默认值，好像原作者没有保存这里的更改。下面又重新选了p）
Selected partition 4
First cylinder (2611-5221, default 2611):
[root@guohuilinuxas31 root]# fdisk /dev/sda
The number of cylinders for this disk is set to 5221.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
(e.g., DOS FDISK, OS/2 FDISK)
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Selected partition 4
First cylinder (2611-5221, default 2611): 2611
Last cylinder or +size or +sizeM or +sizeK (2611-5221, default 5221): 5221
Command (m for help): p
Disk /dev/sda: 42.9 GB, 42949672960 bytes
255 heads, 63 sectors/track, 5221 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 2356 18820147+ 83 Linux
/dev/sda3 2357 2610 2040255 82 Linux swap
/dev/sda4 2611 5221 20972857+ 83 Linux
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.
三、重启系统
reboot
再次查看空间，可以看到free的空间变成了linux的文件格式。
设备号 sda4，没有文件系统。
四、格式化新分配的空间。
[root@guohuilinuxas31 root]# id
uid=0(root) gid=0(root) groups=0(root),1(bin),2(daemon),3(sys),4(adm),6(disk),10(wheel)
[root@guohuilinuxas31 root]# mkfs -t ext3 /dev/sda4(我用的ext4)
mke2fs 1.32 (09-Nov-2002)
warning: 334 blocks unused.
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
2626560 inodes, 5242880 blocks
262160 blocks (5.00%) reserved for the super user
First data block=0
160 block groups
32768 blocks per group, 32768 fragments per group
16416 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000
Writing inode tables: done
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 20 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
[root@guohuilinuxas31 root]# fdisk -l
Disk /dev/sda: 42.9 GB, 42949672960 bytes
255 heads, 63 sectors/track, 5221 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 2356 18820147+ 83 Linux
/dev/sda3 2357 2610 2040255 82 Linux swap
/dev/sda4 2611 5221 20972857+ 83 Linux
可以看到空闲空间为sda4。
五、加载文件系统
[root@guohuilinuxas31 etc]# mount /dev/sda4 /vmware1
[root@guohuilinuxas31 etc]# du -csh /vmware1
20K /vmware1
20K total
[root@guohuilinuxas31 etc]# mount
/dev/sda2 on / type ext3 (rw)
none on /proc type proc (rw)
none on /dev/pts type devpts (rw,gid=5,mode=620)
usbdevfs on /proc/bus/usb type usbdevfs (rw)
/dev/sda1 on /boot type ext3 (rw)
none on /dev/shm type tmpfs (rw)
/dev/sda4 on /vmware1 type ext3 (rw)
[root@guohuilinuxas31 etc]# df -k
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda2 18524524 9287492 8296028 53% /
/dev/sda1 101089 15126 80744 16% /boot
none 1293016 0 1293016 0% /dev/shm
/dev/sda4 20641788 32828 19560320 1% /vmware1
六、自动加载文件系统
[oracle@guohuilinuxas31 etc]$ cat fstab(vi /etc/fstab)
LABEL=/ / ext3 defaults 1 1
LABEL=/boot /boot ext3 defaults 1 2
/dev/sda4 /vmware1 ext3 defaults 1 3
none /dev/pts devpts gid=5,mode=620 0 0
none /proc proc defaults 0 0
none /dev/shm tmpfs defaults 0 0
/dev/sda3 swap swap defaults 0 0
/dev/cdrom /mnt/cdrom udf,iso9660 noauto,owner,kudzu,ro 0 0
/dev/fd0 /mnt/floppy auto noauto,owner,kudzu 0 0