Create an elastic cloud server with the operating system image being CentOS 7.6 64 bit. For more information, see Creating ECS
Create an elastic IP and bind it to the elastic cloud server. For more information, see Purchasing an EIP and Binding ECS Instance
Purchase two 10 GB data disks and mount them to the elastic cloud server. For more information, see Creating EVS and Mounting EVS
If all the preceding resources are successfully created, you can go to the next step to create logical volumes and format the file system.

Operation Steps

The following shows the procedure to create a logical volume using LVM and format the file system in the following three steps:

• Step 1: Install the LVM.

• Step 2: Create a logical volume using LVM.

• Step 3: Create and mount a file system

Step 1: Install the LVM

In the following steps, the operating system is CentOS 7.6 64-bit. The returned information is for reference only.

Log in to the console.
Click in the upper left corner of the console and select a region. In this topic, East China 1 is selected.
Select Compute and click ECS to go to the ECS page.
Locate the row that contains the ECS you want to operate, and in the Operation column, click Remote Login .
Log in to the cloud server as the root user, as shown in the following figure:
Check whether the LVM is installed in the current server before installing the LVM by running the rpm -qa | grep lvm2 command. The information as shown in the following figure is returned:

This returned information indicates that the LVM is not installed in the current server. By default, the LVM is not installed in the ECS.
If the LVM is not installed, run the yum install lvm2command to install the LVM using yum and complete the installation as prompted. The following information is returned:

When "Complete!" is displayed, the installation is complete.
Then run the rpm -qa | grep lvm2 command to check whether the LVM is installed successfully in the cloud server. If the following information is returned, the LVM is successfully installed.

Step 2: Create a logical volume using LVM

After the LVM is installed, you can create logical volumes using LVM. According to the LVM architecture, this level involves three steps:

• Create physical volumes: Initialize EVS partitions or entire hard disk as physical volumes.

• Create a volume group: Add one or more physical volumes to a logical volume group.

• Create logical volumes: Create logical volumes from a logical volume group.

Check that two EVS disks have been mounted to the cloud server before performing this operation.

Log in to the cloud server as the root user, as shown in the following figure:
Run the fdisk -l | grep /dev/vd | grep -v vda command to check the EVS in the cloud server and record the device name. The information as shown in the following figure is returned:

As shown in the figure, two 10 GB data disks /dev/vdb and /dev/vdc have been mounted to the cloud server.
Then, run the pvcreate command to create logical volumes. The pvcreate parameter is the device name. Here, run the pvcreate /dev/vdb /dev/vdc command. The information as shown in the following figure is returned:

As shown in the figure, physical volume /dev/vdb and physical volume /dev/vdc have been created.
Run the pvdisplay command to verify the creation of physical volume /dev/vdb and physical volume /dev/vdc. The information as shown in the following figure is returned:
After physical volumes are created, create a logical volume group. A logical volume group is often created using the vgcreate command. Run the vgcreate vgdata /dev/vdb /dev/vdc command. Wherein, vgdata is the name of the logical volume group, and /dev/vdb and /dev/vdc are the names of physical devices. The information as shown in the following figure is returned:

As shown in the figure, the logical volume group "vgdata" is created.
Run the vgdisplay command to verify the information of the logical volume group vgdata. The information as shown in the following figure is returned:
Finally, create logical volumes by running the lvcreate -L 15GB -n lvdata vgdata command. The command is in the format of lvcreate -L size of logical volume -n name of logical volume name of logical volume name. The parameters are described in details as follows:

· Size of logical volume: The value must be smaller than the available space of the created logical volume group. The unit of capacity can be either MB or GB. In this example, the size of the logical volume is 15 GB.

· Name of logical volume: The name can be customized. In this example, Ivdata is used.

· Name of logic volume group: The name of the created logical volume group. The information as shown in the following figure is returned:
Run the lvdisplay command to check whether logical volumes are successfully created. The information as shown in the following figure is returned:

At this point, logical volumes are successfully created.

Step 3: Create and mount a file system

After a logical volume is created, create a file system on the logical volume and mount the file system to the corresponding directory. In this topic, try to create an "ext4" file system on the logical volume lvdata and mount the file system to the /Data1 path.

Log in to the cloud server as the root user, as shown in the following figure:
Create a file system by running the mkfs.ext4 /dev/vgdata/lvdata command. Wherein, ext4 is the format of the file system, and /dev/vgdat/lvdata is the path of the logical volume created in the "Create a Logical Volume Using LVM" step. The information as shown in the following figure is returned:

When "done" is displayed, the file system is successfully created.
Run the mkdir /Data1 command to create a Data1 directory where the file system will be mounted under the root directory, as shown in the following figure:
Run the mount /dev/vgdata/lvdata /Data1 command to mount the file system lvdata to the /Data1 directory, as shown in the following figure:
Run the mount | grep /Data1 command to check whether the file system is mounted. The information as shown in the following figure is returned:

At this point, the operations of creating logical volumes and formatting the file system using the LVM are complete.

Elastic Volume Service

Creating Resources