测试中遇到这样的情况，vmware虚拟机中增加的 sdb ,可用空间快要满了，需要增加空间，方法记录如下
1. 在VMware上扩展磁盘
在 vmware 虚拟机编辑页面，扩展磁盘的可用空间 (500GB -> 800GB)
2. 重启虚拟机
重启后查看分区是否正确识别，可以看到已经正确识别新的分区大小
# parted /dev/sdb
GNU Parted 3.1
Using /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) p
Model: VMware Virtual disk (scsi)
Disk /dev/sdb: 859GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:
Number Start End Size Type File system Flags
1 1049kB 537GB 537GB primary xfs
(parted) quit
3. 重新分区
删除原来分区，重新创建新的分区
# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Command (m for help): p
Disk /dev/sdb: 859.0 GB, 858993459200 bytes, 1677721600 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: dos
Disk identifier: 0x634e8675
Device Boot Start End Blocks Id System
/dev/sdb1 2048 1048575999 524286976 83 Linux
Command (m for help): d # 删除分区
Selected partition 1
Partition 1 is deleted
Command (m for help): n # 创建新的分区
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p):
Using default response p
Partition number (1-4, default 1):
First sector (2048-1677721599, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-1677721599, default 1677721599):
Using default value 1677721599
Partition 1 of type Linux and of size 800 GiB is set
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 or after you run partprobe(8) or kpartx(8)
Syncing disks.
4. 重启系统，确保分区表被重新读取
5. 扩展分区
首先 mount 新分区，然后使用 xfs_growfs 命令扩展分区
# mount /dev/sdb1 /opt/yum/sample
# xfs_growfs /dev/sdb1
meta-data=/dev/sdb1 isize=512 agcount=4, agsize=32767936 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0 spinodes=0
data = bsize=4096 blocks=131071744, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal bsize=4096 blocks=63999, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 131071744 to 209714944
#如果分区是 ext4 格式需要使用 resize2fs 命令
6. 验证操作
新分区的大小已经变为800G，原来的文件也没有丢失
# df -h
Filesystem Size Used Avail Use% Mounted on
……
/dev/sdb1 800G 433G 368G 55% /opt/yum/sample