Linux Logical Volume Management Operations: Difference between revisions

From NovaOrdis Knowledge Base
Jump to navigation Jump to search
 
(9 intermediate revisions by the same user not shown)
Line 1: Line 1:
=External=
=External=


* https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Logical_Volume_Manager_Administration/index.html
* https://www.howtogeek.com/howto/40702/how-to-manage-and-use-lvm-logical-volume-management-in-ubuntu/
* https://www.howtogeek.com/howto/40702/how-to-manage-and-use-lvm-logical-volume-management-in-ubuntu/
* Step by step guide of using LVM with loopback devices https://ops.tips/blog/lvm-on-loopback-devices/


=Internal=
=Internal=
Line 49: Line 51:
lvmdiskscan -l
lvmdiskscan -l
</pre>
</pre>
=LVM Configuration=
* [[lvmconfig]] - displays LVM configuration.


=Physical Volume Operations=
=Physical Volume Operations=
Line 105: Line 111:
=Procedures=
=Procedures=


* https://www.howtogeek.com/howto/40702/how-to-manage-and-use-lvm-logical-volume-management-in-ubuntu/
* [[Provisioning and Installing a New Filesystem on a New Logical Volume]]
* <span id='Shrinking_the_Filesystem_and_the_Logical_Volume'></span>[[Shringking a File System on a Logical Volume]]
* <span id='Shrinking_a_Logical_Volume_used_by_a_xen_Virtual_Machine'></span>[[Logical Volume Management and Virtualization|Logical Volume Management and Virtualization]]
* [[Provision Docker Storage on a Dedicated Block Device|Provision Thin Pool Strorage for Docker on a Dedicated Block Device]]


==Shrinking the Filesystem and the Logical Volume==
=Troubleshooting=


<font color=red>
* View LVM logs:
This is the simple case, ''it will only work if the logical volume *does not* contain a partition table'':


<pre>
journalctl -u dm-event.service
fsadm
</pre>
 
or
 
<pre>
umount lvm_partition
resize2fs /dev/vg/lv newSize
lvresize -L disksize /dev/vg/lv
resize2fs /dev/vg/lv
</pre>
</font>


==Shrinking a Logical Volume used by a xen Virtual Machine==
* Block devices:


{{Internal|Logical Volume Management and Virtualization|Logical Volume Management and Virtualization}}
[[lsblk]]

Latest revision as of 23:20, 13 February 2018

External

Internal

Overview

Logical volume management commands can be issued from the lvm console, or as standalone commands. For example: 

lvm> lvs

produces identical results to 

lvs

Inventory of Devices that May Be Used as Physical Volumes

lvmdiskscan

Example: 

[root@rhel-test ~]# lvmdiskscan
  /dev/rhel_rhel-test/swap [     820.00 MiB] 
  /dev/sda1                [     500.00 MiB] 
  /dev/rhel_rhel-test/root [       6.67 GiB] 
  /dev/sda2                [       7.51 GiB] LVM physical volume
  /dev/sdb                 [       2.00 GiB] 
  3 disks
  1 partition
  0 LVM physical volume whole disks
  1 LVM physical volume

The output specifies which device is already a LVM Physical Volume

To see only the existing Physical Volumes (devices that have Volume Groups on them) 

lvmdiskscan -l

LVM Configuration

Physical Volume Operations

Physical Volume Concepts

Information about Physical Volumes

  • pvs - provides information about physical volumes available on the system.
  • pvscan - scans all disks for physical volumes.
  • pvdisplay - provides details about a specific physical volume.

Physical Volume Management Operations

  • pvcreate - initializes a physical volume(s) for use by LVM.
  • pvchange - changes attributes of a physical volume.
  • pvresize - resizes a disk or partition in use.
  • pvmove - moves physical extents from one physical volume to another.
  • pvck - checks the consistency of the physical volume metadata.
  • pvremove - removes a physical volume.

Volume Group Operations

Volume Group Concepts

Information about Volume Groups

  • vgs - reports information about volume groups.
  • vgdisplay - display attributes of volume groups.

Volume Group Management Operations

  • vgcreate - create a volume group.
  • vgextend - add Physical Volumes to a Volume Group.
  • vgreduce - removes one or more unused physical volumes from a volume group.
  • vgremove - deletes a volume group.

Logical Volume Operations

Logical Volume

Information about Logical Volumes

  • lvs - provides information about logical volumes available on the system.
  • lvdisplay - displays attributes of a logical volume.
  • lvscan - scans all known volume groups or all supported LVM block devices in the system for defined Logical Volumes.

Logical Volume Management Operations

Procedures

Troubleshooting

  • View LVM logs:
journalctl -u dm-event.service
  • Block devices:
lsblk
Retrieved from "https://kb.novaordis.com/index.php?title=Linux_Logical_Volume_Management_Operations&oldid=38047"