Understanding of Linux practical logic volume LVM

I remember the confusion in my mind when I first came into contact with LVM logical volume management, because I was unable to clearly distinguish the terms involved. After my own experiments, here, I will record my learned experiences and share them with my friends who are new to LVM logical volume management. The biggest advantage of LVM is that it can dynamically adjust the disk space, which is flexible. in Linux system management, we find that the allocation of a partition is unreasonable, if LVM is used for management, we can easily allocate wasted space to other partitions. Www.2cto.com the biggest confusion in understanding LVM management is to distinguish the relationship among PV, VG, and LV. Here I will express the relationship between them. Through the above figure, we can intuitively see the relationship between the three, here we can give a very vivid example to further illustrate, we think of LVM as a steamed bun, in the first step, we need to find the flour. In the figure above, the physical volume is our flour. He directly provides raw materials for steamed bread, we have stirred a lot of flour into the dough to be used in step 2. With the dough, we will drag the steamed bread one by one in step 3, of course, the size of steamed bread is completely controlled by yourself, and finally put in the steamer, then you can open the meal (format the file system, Mount ). A simple analogy makes it difficult to understand the relationship between various colors in the LVM logical volume. At the same time, we can deepen our memory based on the full names of PV, VG, and LV. Www.2cto.com
In the early days, IBM began to provide LVM management mechanisms for the AIX system, and was gradually transplanted to the Linux system. Now we are talking about the second generation of LVM technology, called LVM2, compared with LVM1, the operability is greatly improved. For example, you can directly adjust the volume size online. In the subsequent sections, let's look at the specific implementation process of Shantou.