Centos Kickstart 文件 - 硬盘分区，方便增加硬盘容量

Question 1

您始终可以使用“onboad”工具进行重新创建。删除 fdisk 中的某个部分并不会将其抹去。您只需删除部分，然后在相同的起始扇区重新创建它，但大小要大一些。不要犹豫，在正在运行的挂载分区上执行此操作。它不会破坏任何东西。

但是，要在重新创建后真正使用额外的大小，您仍然需要一种方法来告诉内核重新加载已使用磁盘的部分表，因此您必须安装 parted 并使用 partprobe（当您写入更改并退出时，fdisk 会建议这样做）。它位于存储库内，因此只需 yum install parted 即可。

然后使用 resize2fs 在线扩大文件系统。

VM 内部的 LVM 是不需要的，因为它只会使事情变得更加复杂。（惊喜！）让主机进行实际的物理卷布局管理。

查看记录（实际上它来自 Debian，但对于 CentOS 来说它完全相同）：

root@test:/home/merlin# fdisk -l /dev/sd?
Disk /dev/sda: 8 GiB, 8589934592 bytes, 16777216 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: 0x3bc1a4d0

Device     Boot   Start      End  Sectors  Size Id Type
/dev/sda1          2048  1048575  1046528  511M 82 Linux swap / Solaris
/dev/sda2       1048576 16777215 15728640  7.5G 83 Linux
root@test:/home/merlin# df -h
Файловая система Размер Использовано  Дост Использовано% Cмонтировано в
udev               494M            0  494M            0% /dev
tmpfs              100M         1.7M   98M            2% /run
/dev/sda2          7.4G         921M  6.1G           13% /
tmpfs              499M            0  499M            0% /dev/shm
tmpfs              5.0M            0  5.0M            0% /run/lock
tmpfs              499M            0  499M            0% /sys/fs/cgroup
tmpfs              100M            0  100M            0% /run/user/1000

此时，我在虚拟化主机上的 sda 中添加了 16 Gb。VM 看到：

root@test:/home/merlin# dmesg | tail
[    3.613736] usb 1-1: SerialNumber: 42
[    3.858801] random: crng init done
[    3.927777] hidraw: raw HID events driver (C) Jiri Kosina
[    3.939081] usbcore: registered new interface driver usbhid
[    3.939082] usbhid: USB HID core driver
[    3.963159] input: QEMU QEMU USB Tablet as /devices/pci0000:00/0000:00:01.2/usb1/1-1/1-1:1.0/0003:0627:0001.0001/input/input6
[    3.963623] hid-generic 0003:0627:0001.0001: input,hidraw0: USB HID v0.01 Mouse [QEMU QEMU USB Tablet] on usb-0000:00:01.2-1/input0
[   54.108990] sd 0:0:0:0: Capacity data has changed
[   54.110036] sd 0:0:0:0: [sda] 50331648 512-byte logical blocks: (25.8 GB/24.0 GiB)
[   54.110235] sda: detected capacity change from 8589934592 to 25769803776

现在，整个过程：

root@test:/home/merlin# fdisk -l /dev/sda
Disk /dev/sda: 24 GiB, 25769803776 bytes, 50331648 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: 0x3bc1a4d0

Device     Boot   Start      End  Sectors  Size Id Type
/dev/sda1          2048  1048575  1046528  511M 82 Linux swap / Solaris
/dev/sda2       1048576 16777215 15728640  7.5G 83 Linux
root@test:/home/merlin# fdisk /dev/sda

Welcome to fdisk (util-linux 2.29.2).                                                                                                                                                        
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.


Command (m for help): d
Partition number (1,2, default 2): 2

Partition 2 has been deleted.

Command (m for help): n
Partition type
   p   primary (1 primary, 0 extended, 3 free)
   e   extended (container for logical partitions)
Select (default p): p
Partition number (2-4, default 2): 
First sector (1048576-50331647, default 1048576): 
Last sector, +sectors or +size{K,M,G,T,P} (1048576-50331647, default 50331647): 

Created a new partition 2 of type 'Linux' and of size 23.5 GiB.
Partition #2 contains a ext4 signature.

Do you want to remove the signature? [Y]es/[N]o: n

Command (m for help): p

Disk /dev/sda: 24 GiB, 25769803776 bytes, 50331648 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: 0x3bc1a4d0

Device     Boot   Start      End  Sectors  Size Id Type
/dev/sda1          2048  1048575  1046528  511M 82 Linux swap / Solaris
/dev/sda2       1048576 50331647 49283072 23.5G 83 Linux

Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Re-reading the partition table failed.: Устройство или ресурс занято

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).

root@test:/home/merlin# partprobe /dev/sda
root@test:/home/merlin# df -h
Файловая система Размер Использовано  Дост Использовано% Cмонтировано в
udev               494M            0  494M            0% /dev
tmpfs              100M         1.7M   98M            2% /run
/dev/sda2          7.4G         921M  6.1G           13% /
tmpfs              499M            0  499M            0% /dev/shm
tmpfs              5.0M            0  5.0M            0% /run/lock
tmpfs              499M            0  499M            0% /sys/fs/cgroup
tmpfs              100M            0  100M            0% /run/user/1000
root@test:/home/merlin# resize2fs /dev/sda2
resize2fs 1.43.4 (31-Jan-2017)
Filesystem at /dev/sda2 is mounted on /; on-line resizing required
old_desc_blocks = 1, new_desc_blocks = 3
The filesystem on /dev/sda2 is now 6160384 (4k) blocks long.

root@test:/home/merlin# df -h
Файловая система Размер Использовано  Дост Использовано% Cмонтировано в
udev               494M            0  494M            0% /dev
tmpfs              100M         1.7M   98M            2% /run
/dev/sda2           24G         924M   22G            5% /
tmpfs              499M            0  499M            0% /dev/shm
tmpfs              5.0M            0  5.0M            0% /run/lock
tmpfs              499M            0  499M            0% /sys/fs/cgroup
tmpfs              100M            0  100M            0% /run/user/1000

Answer

您始终可以使用“onboad”工具进行重新创建。删除 fdisk 中的某个部分并不会将其抹去。您只需删除部分，然后在相同的起始扇区重新创建它，但大小要大一些。不要犹豫，在正在运行的挂载分区上执行此操作。它不会破坏任何东西。