完整備份CentOS的硬碟步驟

***請注意分備完後記得要測試系統能正常開機而且相關程式是能正常工作的再作舊硬碟的處置避免發生任何遺憾,本次操作是加入一顆新硬碟的方式操作.
1.確認目前磁碟分割狀態
# ls /dev/sd*
/dev/sda  /dev/sda1  /dev/sda2
2.切換成系統最高權限管理者
# su -
3.fdisk進行新硬碟相關設定
# fdisk /dev/sdb
Command (m for help): c
DOS Compatibility flag is not set
Command (m for help): u
Changing display/entry units to sectors
4.參數p顯示磁碟空間大小,請以實際硬碟大小為準,以下示範例
Command (m for help): p
Disk /dev/sdb: 34.4 GB, 34359738368 bytes
255 heads, 63 sectors/track, 4177 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: 0xd1082b01
   Device Boot      Start         End      Blocks   Id  System
Command (m for help): n
Command action
   e   extended
   p   primary partition (1-4)
5.設定新硬碟相關
p
Partition number (1-4):
Partition number (1-4): 1
First sector (2048-67108863, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-67108863, default 67108863):
Using default value 67108863
6.寫回新硬碟上
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
7.複製系統到新硬碟上
dd if=/dev/sda of=/dev/sdb bs=100M conv=notrunc
8.如果舊硬碟有壞軌在關機後強制使用程式檢查硬碟
# shutdown -rF now