1. 背景
由于目前需要监控的主机较少，（10几台），而且是在Hyper-V上进行部署，因此直接偷懒用官方制作好的ZABBIX应用镜像直接上了。该镜像基本已经配置好，拿来参照官方文档修改一下时区，处理一下字体乱码的问题即可使用。
但该应用镜像磁盘空间很小（10G左右）大概1个多月根目录空间就使用到80%了，因此需要扩容。1
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9appliance@ZABBIX:~$ df -h
Filesystem Size Used Avail Use% Mounted on
udev 2.0G 0 2.0G 0% /dev
tmpfs 395M 5.4M 389M 2% /run
/dev/mapper/zabbix--vg-root 5.1G 4.0G 906M 82% /
tmpfs 2.0G 0 2.0G 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 2.0G 0 2.0G 0% /sys/fs/cgroup
/dev/sda1 472M 62M 386M 14% /boot
2. 具体操作
官方手册只提供了基本步骤，而且没有足够详细的说明，使得我在操作时走了一些弯路，现在将成功的配置记录下来。
2.1 拓展块设备
扩展所使用的虚拟机磁盘镜像的大小，这个直接在虚拟机管理界面操作，很简单，就不多说了。
2.2 创建备份
为防止意外，所有操作都需要可逆。为此可以直接备份数据库，也可以直接创建一个快照作为备份，但在操作成功执行后，最好删除快照，否则硬盘开销会很大。
需要注意，虚拟机快照最好在关闭虚拟机后再进行回滚。
2.3 更改分区大小
Linux更改分区大小且不影响文件，只需要分区的起始柱号与原分区相同就行。后面的操作都基于这一点。
2.3.1 启动 fdisk 更改分区大小。需要以root权限运行:
1 | sudo fdisk /dev/sda |
默认root密码是zabbix。
这样，将在磁盘 sda 上运行 fdisk。
然后，查看当前的分区情况：
执行：1
p
p为显示当前分区信息，例如：1
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17Welcome to fdisk (util-linux 2.27.1).
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/sda: 25 GiB, 26843545600 bytes, 52428800 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
Disklabel type: dos
Disk identifier: 0xf2d29529
Device Boot Start End Sectors Size Id Type
/dev/sda1 * 2048 999423 997376 487M 83 Linux
/dev/sda2 1001470 20477951 19476482 9.3G 5 Extended
/dev/sda5 1001472 20477951 19476480 9.3G 8e Linux LVM
这里可以看到磁盘已经扩到25GB（原来默认是10GB）
2.3.2 重建Extended分区
后面的操作就将sda2删除，并重建sda5分区。1
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9Command (m for help): d
Partition number (1,2,5, default 5): 5
Partition 5 has been deleted.
Command (m for help): d
Partition number (1,2, default 2): 2
Partition 2 has been deleted.
新建分区：1
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10Command (m for help): n
Partition type
p primary (1 primary, 0 extended, 3 free)
e extended (container for logical partitions)
Select (default p): e
Partition number (2-4, default 2): 2
First sector (999424-52428799, default 999424):
Last sector, +sectors or +size{K,M,G,T,P} (999424-52428799, default 52428799):
Created a new partition 2 of type 'Extended' and of size 24.5 GiB.
重建sda2分区时，分区Last sector使用最大大小，即包含了扩展出来的空间。
接着重建sda5,这里为了直观，使用“u”来令分区数目取代柱面数目，来表示每个分区的起始地址。1
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23Command (m for help): u
Changing display/entry units to cylinders (DEPRECATED!).
Command (m for help): p
Disk /dev/sda: 25 GiB, 26843545600 bytes, 52428800 sectors
Geometry: 255 heads, 63 sectors/track, 3263 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
Disklabel type: dos
Disk identifier: 0xf2d29529
Device Boot Start End Cylinders Size Id Type
/dev/sda1 * 1 63 63 487M 83 Linux
/dev/sda2 63 3264 3202 24.5G 5 Extended
Command (m for help): n
All space for primary partitions is in use.
Adding logical partition 5
First cylinder (63-3264, default 63):
Last cylinder, +cylinders or +size{K,M,G,T,P} (63-3264, default 3264): 1279
Created a new partition 5 of type 'Linux' and of size 9.3 GiB.
接着将分区5的分区类型修改回原来的类型：1
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19Command (m for help): t
Partition number (1,2,5, default 5): 5
Partition type (type L to list all types): 8e
Changed type of partition 'Linux' to 'Linux LVM'.
Command (m for help): p
Disk /dev/sda: 25 GiB, 26843545600 bytes, 52428800 sectors
Geometry: 255 heads, 63 sectors/track, 3263 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
Disklabel type: dos
Disk identifier: 0xf2d29529
Device Boot Start End Cylinders Size Id Type
/dev/sda1 * 1 63 63 487M 83 Linux
/dev/sda2 63 3264 3202 24.5G 5 Extended
/dev/sda5 63 1279 1217 9.3G 8e Linux LVM
2.3.3 新建分区用做扩展
接着新建一个分区sda6:1
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22Command (m for help): n
All space for primary partitions is in use.
Adding logical partition 6
First cylinder (1280-3264, default 1280):
Last cylinder, +cylinders or +size{K,M,G,T,P} (1280-3264, default 3264):
Created a new partition 6 of type 'Linux' and of size 15.2 GiB.
Command (m for help): p
Disk /dev/sda: 25 GiB, 26843545600 bytes, 52428800 sectors
Geometry: 255 heads, 63 sectors/track, 3263 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
Disklabel type: dos
Disk identifier: 0xf2d29529
Device Boot Start End Cylinders Size Id Type
/dev/sda1 * 1 63 63 487M 83 Linux
/dev/sda2 63 3264 3202 24.5G 5 Extended
/dev/sda5 63 1279 1217 9.3G 8e Linux LVM
/dev/sda6 1280 3264 1985 15.2G 83 Linux
至此便完成分区的修改，执行“w”进行修改的应用,并重新启动。1
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8Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Re-reading the partition table failed.: 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).
appliance@ZABBIX:~$ sudo shutdown -r hownow
2.4 分区扩展操作
下面执行扩展的操作：
新建物理卷：1
2appliance@ZABBIX:~$ sudo pvcreate /dev/sda6
Physical volume "/dev/sda6" successfully created
查看新物理卷：1
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12appliance@ZABBIX:~$ sudo pvdisplay /dev/sda6
"/dev/sda6" is a new physical volume of "15.20 GiB"
--- NEW Physical volume ---
PV Name /dev/sda6
VG Name
PV Size 15.20 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID 59XWOV-1x84-iF55-vd8y-xnbl-fSZ0-0gfSKc
检查可用的物理卷。这里必须有两个卷：zabbix-vg 和新创建的：1
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4appliance@ZABBIX:~$ sudo pvs
PV VG Fmt Attr PSize PFree
/dev/sda5 zabbix-vg lvm2 a-- 9.29g 0
/dev/sda6 lvm2 --- 15.20g 15.20g
用新创建的物理卷扩展现有的卷组:1
2appliance@ZABBIX:~$ sudo vgextend zabbix-vg /dev/sda6
Volume group "zabbix-vg" successfully extended
检查 “zabbix-vg” 卷组:1
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21appliance@ZABBIX:~$ sudo vgsidisplay
--- Volume group ---
VG Name zabbix-vg
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 24.48 GiB
PE Size 4.00 MiB
Total PE 6268
Alloc PE / Size 2377 / 9.29 GiB
Free PE / Size 3891 / 15.20 GiB
VG UUID DhcHCt-7Vi8-FYxM-HZTe-Qm1Z-l3px-BhteCN
使用空闲的 PE 空间扩展你的逻辑卷:1
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3appliance@ZABBIX:~$ sudo lvextend -l +100%FREE /dev/mapper/zabbix--vg-root
Size of logical volume zabbix-vg/root changed from 5.29 GiB (1353 extents) to 20.48 GiB (5244 extents).
Logical volume root successfully resized.
重新分配 root 卷空间 (可在系统中实时完成):1
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15appliance@ZABBIX:~$ sudo resize2fs /dev/mapper/zabbix--vg-root
resize2fs 1.42.13 (17-May-2015)
Filesystem at /dev/mapper/zabbix--vg-root is mounted on /; on-line resizing required
old_desc_blocks = 1, new_desc_blocks = 2
The filesystem on /dev/mapper/zabbix--vg-root is now 5369856 (4k) blocks long.
appliance@ZABBIX:~$ df -h
Filesystem Size Used Avail Use% Mounted on
udev 2.0G 0 2.0G 0% /dev
tmpfs 395M 5.4M 389M 2% /run
/dev/mapper/zabbix--vg-root 21G 4.0G 16G 21% /
tmpfs 2.0G 0 2.0G 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 2.0G 0 2.0G 0% /sys/fs/cgroup
/dev/sda1 472M 62M 386M 14% /boot
此时检查root分区已经成功扩展。
