This may take a while No volume groups found Make any previously set up volume groups available sudo vgchange -a y Prepare the partitions. A volume group is the result of combining several physical units into a single logical device. It can be done with a single command, but, as an example, we will create our volume group and extend it. Code Listing 2. Logical volumes are the equivalent of partitions you would create using fdisk in a non LVM2 environment.
However, it is easier to enlarge partitions than it is to shrink them, so it is best to start smaller and add space as needed. For a nice GUI, you can run system-config-lvm from the shell. This will let you manage your LVM volume groups more easily. However, be careful, as changes are made immediately and you don't want to accidentally wipe your data. After you press the 'Forward' button, go to picture 1. See picture 1. Press the "Change Again, the file system is your choice and doesn't need to be ext4.
See pictures 1. This installation will ask for you additional information like your timezone, username, etc Once you are done, you can sit back and wait for the whole thing to comeplete. Once the installation process is complete, you will see picture 1.
You want to press the "Continue Testing" so you can continue to step 7. To fix that we need to install it onto your newly set up Ubuntu instance. The commands below will help do this.
Mounting your home file system probably isn't necessary but doesn't hurt to do. Doing this will make any installations and changes perminant onto your changed root filesystem.
Now that we are on your Ubuntu instance, you will noticed that you are now root and the symbole after 'root ubuntu:' has changed to a.
That is a good thing as we are not on the live CD's root file system but on your instance of Ubuntu. Get the latest tutorials on SysAdmin and open source topics. Hollie's Hub for Good Supporting each other to make an impact.
Write for DigitalOcean You get paid, we donate to tech non-profits. LVM , or Logical Volume Management, is a storage device management technology that gives users the power to pool and abstract the physical layout of component storage devices for easier and flexible administration.
Utilizing the device mapper Linux kernel framework, the current iteration, LVM2, can be used to gather existing storage devices into groups and allocate logical units from the combined space as needed. In this guide, we will cover how to manage your storage devices with LVM. We will show you how to display information about volumes and potential targets, how to create and destroy volumes of various types, and how to modify existing volumes through resizing or transformation. We will be using an Ubuntu In order to follow along, you should have access to an Ubuntu You will need to have a non-root user with sudo privileges configured for administrative tasks.
You can follow our Ubuntu It is important to be able to get information about the various LVM components in your system easily. Fortunately, the LVM tool suite provides an abundant amount of tools for displaying information about every layer in the LVM stack. To display all of the available block storage devices that LVM can potentially manage, use the lvmdiskscan command:.
A header is written to storage devices to mark them as free to use as LVM components. Devices with these headers are called physical volumes. You can display all of the physical devices on your system by using lvmdiskscan with the -l option, which will only return physical volumes:.
The pvscan command is fairly similar to the above, in that it searches all available devices for LVM physical volumes. The output format is a bit different and it include a small amount of additional information:. If you need more detail, the pvs and pvdisplay commands are better options. The pvs command is highly configurable and can display information in many different formats. Because its output can be tightly controlled, it is frequently used in when scripting or automation is needed.
Its basic output provides a useful at-a-glance summary similar to the earlier commands:. For more verbose, human-readable output, the pvdisplay command is usually a better option:. As you can see the pvdisplay command is often the easiest command for getting detailed information about physical volumes.
To discover the logical extents that have been mapped to each volume, pass in the -m option to pvdisplay :. This can be very useful when trying to determine which data is held on which physical disk for management purposes. The vgscan command can be used to scan the system for available volume groups.
It also rebuilds the cache file when necessary. It is a good command to use when you are importing a volume group into a new system:. The command does not output very much information, but it should be able to find every available volume group on the system.
To display more information, the vgs and vgdisplay commands are available. Like its physical volume counterpart, the vgs command is versatile and can display a large amount of information in a variety of formats. Because its output can be manipulated easily, it is frequently used in when scripting or automation is needed. For example, some helpful output modifications are to show the physical devices and the logical volume path:.
For more verbose, human-readable output, the vgdisplay command is a usually the best choice. Adding the -v flag also provides information about the physical volumes the volume group is built upon, and the logical volumes that were created using the volume group:. The vgdisplay command is useful because it can tie together information about many different elements of the LVM stack. As with the other LVM components, the lvscan option scans the system and outputs minimal information about the logical volumes it finds:.
For more complete information, the lvs command is flexible, powerful, and easy to use in in scripts:. To find out about the number of stripes and the logical volume type, use the --segments option:. When the -m flag is added, the tool will also display information about how the logical volume is broken down and distributed:. This information is useful if you need to remove that underlying device and wish to move the data off to specific locations.
This section will discuss how to create and expand physical volumes, volume groups, and logical volumes. In order to use storage devices with LVM, they must first be marked as a physical volume. This specifies that LVM can use the device within a volume group. First, use the lvmdiskscan command to find all block devices that LVM can see and use:.
Warning : Make sure that you double-check that the devices you intend to use with LVM do not have any important data already written to them.
Using these devices within LVM will overwrite the current contents.
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