All the time Hyper-V Linux Disk expansion of virtual host is troublesome. Today we will introduce how to use fdisk and resize2fs Data disk capacity expansion.

Description:

Host system: Windows Server 2012 R2 Hyper-V
Virtual host: CentOS Linux release 7.4.1708 (Core)

Usual contact Hyper-V More, so disk expansion is common. Windwos Disk expansion is the simplest. This article will not cover it.
Today I will Centos The virtual host performs the demonstration. The small machine is divided into two disks (both independent disks), and one is the system disk /dev/sda , the other is the database disk /dev/sdb The current requirement is that SDB should change from the original 30GB Expand to 100GB 。

1. Check the disk partition and mounting status before capacity expansion

 [ root@renwole-com  ~]# fdisk -l Disk /dev/sdb: 32.2 GB, 32212254720 bytes, 62914560 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk label type: dos Disk identifier: 0x5f149419 Device Boot      Start         End      Blocks   Id  System /dev/sdb1            2048    62914559    31456256   83   Linux Disk /dev/sda: 10.7 GB, 10737418240 bytes, 20971520 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk label type: dos Disk identifier: 0x00043041 Device Boot      Start         End      Blocks   Id  System /dev/sda1   *        2048     2099199     1048576   83   Linux /dev/sda2         2099200    20971519     9436160   8e   Linux LVM Disk /dev/mapper/cl-root: 8585 MB, 8585740288 bytes, 16769024 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk /dev/mapper/cl-swap: 1073 MB, 1073741824 bytes, 2097152 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes

 [ root@renwole-com  ~]# df -hT Filesystem          Type      Size  Used Avail Use% Mounted on /dev/mapper/cl-root xfs       8.0G  950M  7.1G  12% / devtmpfs            devtmpfs  1.9G     0  1.9G   0% /dev tmpfs               tmpfs     1.9G     0  1.9G   0% /dev/shm tmpfs               tmpfs     1.9G  8.3M  1.9G   1% /run tmpfs               tmpfs     1.9G     0  1.9G   0% /sys/fs/cgroup /dev/sda1            xfs      1014M  138M  877M  14% /boot tmpfs               tmpfs     379M     0  379M   0% /run/user/0 /dev/sdb1            ext4       30G   60M   28G   1% /apps

Note: orange part /dev/sdb1 Partition size is 30GB , which is also attached 30GB 。

2. Unload and mount

delete /etc/fstab The following boot disk auto mount information in the file:

/dev/sdb1 /apps ext4 defaults 0 0

3. Start virtual host disk expansion

Hyper-V virtual machine operations:

open Hyper-V Manager, find the small machine that needs to be expanded and shut down, then right-click Settings, click the disk that needs to be expanded, (usually the data disk) Edit - Next by default - Select Next by extension, this step needs attention, assuming that your original disk is 30G , then you want to expand to 100G , please fill in one hundred Click Next to finish. Then start the virtual host.

View the disk partitions after capacity expansion:

 [ root@renwole-com  ~]# fdisk -l Disk /dev/sda: 10.7 GB, 10737418240 bytes, 20971520 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk label type: dos Disk identifier: 0x00043041 Device Boot      Start         End      Blocks   Id  System /dev/sda1   *        2048     2099199     1048576   83   Linux /dev/sda2         2099200    20971519     9436160   8e   Linux LVM Disk /dev/sdb: 107.4 GB, 107374182400 bytes, 209715200 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk label type: dos Disk identifier: 0x5f149419 Device Boot      Start         End      Blocks   Id  System /dev/sdb1            2048    62914559    31456256   83   Linux Disk /dev/mapper/cl-root: 8585 MB, 8585740288 bytes, 16769024 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk /dev/mapper/cl-swap: 1073 MB, 1073741824 bytes, 2097152 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes

sdb The partition size is changed from the original 30GB Expand to 100GB , but partition sdb1 No capacity expansion is used 70GB What about space?

4. Delete partition

Delete different partitions, delete data, delete partitions and rebuild them:

 [ root@renwole-com  ~]# fdisk /dev/sdb The device presents a logical sector size that is smaller than the physical sector size. Aligning to a physical sector (or optimal I/O) size boundary is recommended, or performance may be impacted. 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): d #Delete sdb1 partition Selected partition 1 Partition 1 is deleted Command (m for help): n #New Section Partition type: p   primary (0 primary, 0 extended, 4 free) e   extended Select (default p): p Partition number (1-4,  default 1): one #Specify partition code First sector (2048-209715199,  default 2048): Using default value 2048 Last sector, +sectors or +size{K, M,G} (2048-209715199,  default 209715199): Using default value 209715199 Partition 1 of type Linux and of size 100 GiB is set Command (m for help): w #Enter w to save The partition table has been altered! Calling ioctl() to re-read partition table. Syncing disks.

Check the disk partition again

 [ root@renwole-com  ~]# fdisk -l ... Disk /dev/sdb: 107.4 GB, 107374182400 bytes, 209715200 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk label type: dos Disk identifier: 0x5f149419 Device Boot      Start         End      Blocks   Id  System /dev/sdb1            2048   209715199   104856576   83   Linux ...

Has changed from the original 30G Expand to 100G However, it can't be used yet. The following operations are required to ensure successful capacity expansion:

 [ root@renwole-com  ~]# resize2fs -f /dev/sdb1 resize2fs 1.42.9 (28-Dec-2013) Resizing the filesystem on /dev/sdb1 to 26214144 (4k) blocks. The filesystem on /dev/sdb1 is now 26214144 blocks long.

Capacity expansion succeeded.

5. Attach the disk

 [ root@renwole-com  ~]# mount /dev/sdb1 /apps/ [ root@renwole-com  ~]# df -hT Filesystem          Type      Size  Used Avail Use% Mounted on /dev/mapper/cl-root xfs       8.0G  950M  7.1G  12% / devtmpfs            devtmpfs  1.9G     0  1.9G   0% /dev tmpfs               tmpfs     1.9G     0  1.9G   0% /dev/shm tmpfs               tmpfs     1.9G  8.3M  1.9G   1% /run tmpfs               tmpfs     1.9G     0  1.9G   0% /sys/fs/cgroup /dev/sda1            xfs      1014M  138M  877M  14% /boot tmpfs               tmpfs     379M     0  379M   0% /run/user/0 /dev/sdb1            ext4       99G   60M   94G   1% /apps [ root@renwole-com  ~]# ls /apps/ web  mysql

As shown above, The data disk of the Linux virtual host has been successfully expanded. Check that the data is not lost.

In addition, write your disk information to /etc/fstab File, otherwise the disk needs to be manually mounted after reboot.

Note: In the same sentence, before operating any data, you must first back it up to form a good habit to prevent data loss.