前几天收到需求，在阿里云上购买5台服务器，配置为32G,8核,3T
问题主要是卡在这里，阿里云的公共镜像里 Centos 7.3 默认为 EXT4 文件系统，和官方的不同，官网默认文件系统为 XFS 。而 EXT4 文件系统默认最大只支持最大分区为2TB，这里有3TB，如果用 EXT4 文件系统，就表示剩余的1TB空间会被浪费… 

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[root@bigdata1 ~]# fdisk -l /dev/vdb 
Disk /dev/vdb: 3298.5 GB, 3298534883328 bytes, 6442450944 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
[root@bigdata1 ~]#

这时默认的fdisk分区工具将无法使用了，因为它不能满足我们的需求，这里就需要用到 parted 分区工具了

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#分区命令
parted /dev/vdb
mklabel
gpt
mkpart
xfs
0G
3299GB
p
quit

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[root@bigdata1 ~]# parted /dev/vdb 
GNU Parted 3.1
Using /dev/vdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) p                                                                
Error: /dev/vdb: unrecognised disk label
Model: Virtio Block Device (virtblk)                                      
Disk /dev/vdb: 3299GB
Sector size (logical/physical): 512B/512B
Partition Table: unknown
Disk Flags: 
(parted) help                                                             
  align-check TYPE N                        check partition N for TYPE(min|opt) alignment
  help [COMMAND]                           print general help, or help on COMMAND
  mklabel,mktable LABEL-TYPE               create a new disklabel (partition table)
  mkpart PART-TYPE [FS-TYPE] START END     make a partition
  name NUMBER NAME                         name partition NUMBER as NAME
  print [devices|free|list,all|NUMBER]     display the partition table, available devices, free space, all found
        partitions, or a particular partition
  quit                                     exit program
  rescue START END                         rescue a lost partition near START and END
  rm NUMBER                                delete partition NUMBER
  select DEVICE                            choose the device to edit
  disk_set FLAG STATE                      change the FLAG on selected device
  disk_toggle [FLAG]                       toggle the state of FLAG on selected device
  set NUMBER FLAG STATE                    change the FLAG on partition NUMBER
  toggle [NUMBER [FLAG]]                   toggle the state of FLAG on partition NUMBER
  unit UNIT                                set the default unit to UNIT
  version                                  display the version number and copyright information of GNU Parted
(parted) mklabel                                                          
New disk label type? gpt                                                  
(parted) p                                                                
Model: Virtio Block Device (virtblk)
Disk /dev/vdb: 3299GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags: 
Number  Start  End  Size  File system  Name  Flags
(parted) mkpart                                                           
Partition name?  []? ?                                                    
File system type?  [ext2]? xfs
Start? 0G                                                                 
End? 3299GB                                                               
(parted) p                                                                
Model: Virtio Block Device (virtblk)
Disk /dev/vdb: 3299GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags: 
Number  Start   End     Size    File system  Name  Flags
 1      1049kB  3299GB  3299GB               ?
(parted) quit                                                             
Information: You may need to update /etc/fstab.
[root@bigdata1 ~]#

然后格式化为 xfs 文件系统后挂载

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[root@bigdata1 ~]# mkfs.xfs /dev/vdb1 
meta-data=/dev/vdb1              isize=512    agcount=4, agsize=201326464 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=0, sparse=0
data     =                       bsize=4096   blocks=805305856, imaxpct=5
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal log           bsize=4096   blocks=393215, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
[root@bigdata1 ~]#
[root@bigdata1 ~]# blkid /dev/vdb1
/dev/vdb1: UUID="32687403-bcc8-425f-8544-ddf710186d53" TYPE="xfs" PARTLABEL="?" PARTUUID="580a257e-18e2-4d57-99cf-b5be5b6
9557a" [root@bigdata1 ~]#
[root@bigdata1 ~]# mkdir /data
[root@bigdata1 ~]# tail -1 /etc/fstab 
UUID="32687403-bcc8-425f-8544-ddf710186d53"	/data		xfs	defaults	0 0
[root@bigdata1 ~]# mount -a

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[root@bigdata1 ~]# fdisk -l /dev/vdb
WARNING: fdisk GPT support is currently new, and therefore in an experimental phase. Use at your own discretion.
Disk /dev/vdb: 3298.5 GB, 3298534883328 bytes, 6442450944 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: gpt
#         Start          End    Size  Type            Name
 1         2048   6442448895      3T  Microsoft basic ?
[root@bigdata1 ~]#
[root@bigdata1 ~]# df -T /dev/vdb1 
Filesystem     Type  1K-blocks  Used  Available Use% Mounted on
/dev/vdb1      xfs  3219650564 32944 3219617620   1% /data
[root@bigdata1 ~]#

这时我们就可以在 Centos 7.3(默认为ext4)上使用大磁盘了(超过2TB)

参考：https://help.aliyun.com/document_detail/34377.html

本文出自”Jack Wang Blog”：http://www.yfshare.vip/2017/07/15/怎么在Linux划分大磁盘分区/