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在linux下磁盘分区大于2T的时候,是不能使用常用fdisk命令来进行分区的，只能使用gpt工具来处理。
原因是:在Linux中，由于ext3文件系统不支持大于2TB的分区，所以要使用GPT分区格式。
1.查看当前磁盘信息大小为5T，
[root@zhixin ~]# fdisk -l /dev/sdb WARNING: GPT (GUID Partition Table) detected on '/dev/sdb'! The util fdisk doesn't support GPT. Use GNU Parted.' Disk /dev/sdb: 5399.2 GB, 5399176544256 bytes 255 heads, 63 sectors/track, 656412 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x00000000
2.使用fidsk分区
最大可用为2T
[root@zhixin zhixintech]# df -lh Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_j9odb2-root 99G 8.8G 85G 10% / tmpfs 127G 224K 127G 1% /dev/shm /dev/sda1 9.8G 60M 9.2G 1% /boot /dev/sdb1 2.0T 71M 1.9T 1% /backup
3.使用gpt分区
[root@zhixin zhixintech]# parted /dev/sdb GNU Parted 2.1 Using /dev/sdb Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) help align-check TYPE N check partition N for TYPE(min|opt) alignment check NUMBER do a simple check on the file system cp [FROM-DEVICE] FROM-NUMBER TO-NUMBER copy file system to another partition help [COMMAND] print general help, or help on COMMAND mklabel,mktable LABEL-TYPE create a new disklabel (partition table) mkfs NUMBER FS-TYPE make a FS-TYPE file system on partition NUMBER mkpart PART-TYPE [FS-TYPE] START END make a partition mkpartfs PART-TYPE FS-TYPE START END make a partition with a file system move NUMBER START END move partition NUMBER 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 resize NUMBER START END resize partition NUMBER and its file system rm NUMBER delete partition NUMBER select DEVICE choose the device to edit 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 gpt --执行命令mklabel gpt，把sdb改成gpt大分区格式 Warning: The existing disk label on /dev/sdb will be destroyed and all data on this disk will be lost. Do you want to continue? Yes/No? yes
(parted) mkpart primary 0 5399gb 创建一个主分区，容量从0gb开始到5399gb的全部空间。 Warning: The resulting partition is not properly aligned for best performance. Ignore/Cancel? cancel
--注意警告，但是事关性能的问题，由于在分区时起始扇区设置不合理，导致了出现这样的警告。
根据google来的方法：
原文链接：http://rainbow.chard.org/2013/01/30/how-to-align-partitions-for-best-performance-using-parted/
[root@zhixin ~]# cat /sys/block/sdb/queue/optimal_io_size 0 --我这里是0，原文是1048576 [root@zhixin ~]# cat /sys/block/sdb/queue/minimum_io_size 4096 [root@zhixin ~]# [root@zhixin ~]# cat /sys/block/sdb/alignment_offset 0 [root@zhixin ~]# cat /sys/block/sdb/queue/physical_block_size 4096
如果optimal_io_size不为0,暂定是1048576，则可以用optimal_io_size的值加上alignment_offset的值，
然后除以physical_block_size的值，就是起始扇区的位置了，如上面的例子中，可以用这个公式算出来起始扇区的设定值：
(1048576 + 0) / 512 = 2048
如果optimal_io_size为0，那么我们最好直接使用起始扇区的默认值2048。
最后在分区的时候使用以下的命令就可以了：
(parted) mkpart primary 2048s 100%
(不要忘记2048后的s单位)
此时分区后就不会出现The resulting partition is not properly aligned for best performance的警告了。
原文有个评论：可以参考一下
Apparently, using % causes parted to automatically align the sectors for best performance: (parted) mkpart primary ext4 0% 100%
(parted) print --打印一下看看分区结果，没有问题。 Model: DELL PERC H730 Mini (scsi) Disk /dev/sdb: 5399GB Sector size (logical/physical): 512B/4096B Partition Table: gpt Number Start End Size File system Name Flags 1 1049kB 5399GB 5399GB primary quit退出
4.格式化分区
[root@zhixin zhixintech]# mkfs.ext4 -F /dev/sdb1
5.挂载到目录
[root@zhixin zhixintech]# mount /dev/sdb1 /backup/ [root@zhixin zhixintech]# df -lh Filesystem Size Used Avail Use% Mounted on /dev/mapper/vg_j9odb2-root 99G 8.8G 85G 10% / tmpfs 127G 224K 127G 1% /dev/shm /dev/sda1 9.8G 60M 9.2G 1% /boot /zhixintech/rhel-server-6.7-x86_64-dvd.iso 3.6G 3.6G 0 100% /mnt /dev/sdb1 4.9T 61M 4.6T 1% /backup --5T
5.加入开机自启动
[root@zhixin zhixintech]# cat /etc/fstab |grep /dev/sdb1 /dev/sdb1 /backup ext4 defaults 0 0
OK。。。搞定了。
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gpt分区
