Linux札记2-esxi上为基于基于LVM的centos7的根目录扩容
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概念:据说默认centos都是基于LVM的
LVM:LVM是逻辑盘卷管理(Logical Volume Manager)的简称,它是Linux环境下对磁盘分区进行管理的一种机制.
LVM 更加详细的说明可点这里:http://www.cnblogs.com/mchina/p/linux-centos-logical-volume-manager-lvm.html
fdisk 命令用法http://blog.sina.com.cn/s/blog_66b448620100ibay.html
查看磁盘空间,根目录太小了,希望增加磁盘
在vsphere上修改磁盘的大小,重启进来。
[root@ucx-auto ~]# df -lh
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 30G 23G 7.1G 76% /
devtmpfs 5.8G 0 5.8G 0% /dev
tmpfs 5.8G 0 5.8G 0% /dev/shm
tmpfs 5.8G 8.9M 5.8G 1% /run
tmpfs 5.8G 0 5.8G 0% /sys/fs/cgroup
/dev/sda1 497M 155M 343M 32% /boot
tmpfs 1.2G 0 1.2G 0% /run/user/0
一。查看下LV
[root@ucx-auto ~]# lvdisplay
--- Logical volume ---
LV Path /dev/centos/swap
LV Name swap
VG Name centos
LV UUID trGefC-4mxg-BkS6-sywT-ie3O-deA3-WC0EDQ
LV Write Access read/write
LV Creation host, time localhost, 2016-07-26 17:38:31 +0800
LV Status available
# open 2
LV Size 2.02 GiB
Current LE 516
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
--- Logical volume ---
LV Path /dev/centos/root
LV Name root
VG Name centos
LV UUID MRmrQV-MDKZ-ZJbQ-cvDP-nMEY-hWJk-xFCceo
LV Write Access read/write
LV Creation host, time localhost, 2016-07-26 17:38:31 +0800
LV Status available
# open 1
LV Size 66.49 GiB
Current LE 17022
Segments 2
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:1
二:查看机器所挂硬盘个数及分区情况
[root@ucx-auto ~]# fdisk -l
Disk /dev/sda: 75.2 GB, 75161927680 bytes, 146800640 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: 0x000cfb48
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 1026047 512000 83 Linux
/dev/sda2 1026048 67108863 33041408 8e Linux LVM
Disk /dev/mapper/centos-swap: 2164 MB, 2164260864 bytes, 4227072 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 /dev/mapper/centos-root: 31.7 GB, 31666995200 bytes, 61849600 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
如上 有一块磁盘/dev/sda 有两个分区。就用了33G,说明还有未分区的
三:/dev/sda进行分区,做这个时候忘记截图了 ,大概是下面这样,如果让你输入分区号,顺延下去即可。
![](https://images2018.cnblogs.com/blog/1003452/201803/1003452-20180305161727253-1938142025.png)
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.
![](https://images2018.cnblogs.com/blog/1003452/201803/1003452-20180305164005341-1484298403.png)
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
2490368 inodes, 9961472 blocks
498073 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
304 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information:
done
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
root centos -wi-ao---- 29.49g
swap centos -wi-ao---- 2.02g
WARNING: ext3 signature detected on /dev/sda3 at offset 1080. Wipe it? [y/n]: ^C Interrupted...
Aborted wiping of ext3.
1 existing signature left on the device.
Aborting pvcreate on /dev/sda3.
[root@ucx-auto dev]# pvcreate /dev/sda3
WARNING: ext3 signature detected on /dev/sda3 at offset 1080. Wipe it? [y/n]:
WARNING: ext3 signature detected on /dev/sda3 at offset 1080. Wipe it? [y/n]: y
Wiping ext3 signature on /dev/sda3.
Physical volume "/dev/sda3" successfully created
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 30G 23G 7.1G 76% /
devtmpfs 5.8G 0 5.8G 0% /dev
tmpfs 5.8G 0 5.8G 0% /dev/shm
tmpfs 5.8G 8.9M 5.8G 1% /run
tmpfs 5.8G 0 5.8G 0% /sys/fs/cgroup
/dev/sda1 497M 155M 343M 32% /boot
tmpfs 1.2G 0 1.2G 0% /run/user/0
Invalid volume group name centos/root.
Run `vgextend --help' for more information.
[root@ucx-auto dev]# vgextend /dev/mapper/centos /dev/sda3
Volume group "centos" successfully extended
--- Volume group ---
VG Name centos
System ID
Format lvm2
Metadata Areas 2
Metadata Sequence No 4
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 2
Open LV 2
Max PV 0
Cur PV 2
Act PV 2
VG Size 69.50 GiB
PE Size 4.00 MiB
Total PE 17793
Alloc PE / Size 8066 / 31.51 GiB 分配的
Free PE / Size 9727 / 38.00 GiB 空闲的
VG UUID 8iYw2C-aqVR-C0eb-nRF4-v9q7-ZEyh-pxrRQB
Size of logical volume centos/root changed from 29.49 GiB (7550 extents) to 66.49 GiB (17022 extents).
Logical volume root successfully resized.
e2fsck 1.42.9 (28-Dec-2013)
/dev/mapper/centos-root is mounted.
e2fsck: Cannot continue, aborting.
resize2fs 1.42.9 (28-Dec-2013)
resize2fs: Bad magic number in super-block while trying to open /dev/mapper/centos-root
Couldn't find valid filesystem superblock.
3.换个姿势再来一次
[root@ucx-auto dev]# xfs_growfs /dev/mapper/centos-root
meta-data=/dev/mapper/centos-root isize=256 agcount=4, agsize=1932800 blks
= sectsz=512 attr=2, projid32bit=1
= crc=0 finobt=0
data = bsize=4096 blocks=7731200, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=0
log =internal bsize=4096 blocks=3775, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
data blocks changed from 7731200 to 17430528
4.看到根目录已经扩大了
[root@ucx-auto dev]# df -lh
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 67G 23G 45G 34% /
devtmpfs 5.8G 0 5.8G 0% /dev
tmpfs 5.8G 0 5.8G 0% /dev/shm
tmpfs 5.8G 8.9M 5.8G 1% /run
tmpfs 5.8G 0 5.8G 0% /sys/fs/cgroup
/dev/sda1 497M 155M 343M 32% /boot
tmpfs 1.2G 0 1.2G 0% /run/user/0