LVM | Forrest’s 博客

type

status

date

slug

summary

存储的分类

按照物理介质分类

机械硬盘 HDD

特点：磁盘旋转存储，成本低，容量大，速度较慢（寻道时间影响数据的访问速度
优点：适合海量数据的存储）（冷数据、归档
缺点：随机读写性能差

固态硬盘SSD

特点：基于闪存芯片，随机读写性能强
优点：低延迟、高性能
缺点：成本高，写入寿命有限（芯片写入次数寿命有限

按照存储结构分类

block storage

数据已固定的块设备存储和访问
适合场景：数据库、虚拟机磁盘
实例：传统SAN存储、iSCSI卷

file storage

基于块设备，构建文件系统（ext4、xfs）
数据通过文件路径访问，支持文件系统层级结构
适合场景：共享路径、文档存储
实例：NFS

object storage

非结构化数据
数据通过唯一的对象id访问，元数据可以扩展
适合场景：海量非结构化数据，比图片、视频
实例：AWS的s3（simple storage service, ceph object

network storage device

通过网络协议（NFS、iSCSI、CephFS）访问远程存储资源
存储的底层可以块设备或文件设备，支持集中化管理

文件系统类型

ext4(fourth extended file system

提供日志功能（journaling）：减少意外关机导致的数据损坏
支持大文件和大分区
广泛应用于linux的服务器和桌面系统
是linux的默认文件系统之一

高性能日志文件系统，支持超大文件和分区
支持并发I/O操作，适合多线程读写
设计注重高吞吐和低延迟
支持实时子卷（real-time-subvolume），提供了更加细粒度的大磁盘I/O控制

LVM是什么

LVM（Logical Volume Manager）是 Linux 中的一种逻辑卷管理工具，它通过将物理磁盘分割成更灵活的逻辑卷，提供了更高效的磁盘空间管理方式。LVM的优势在于支持在线扩展和调整存储，不需要重启或大规模停机，非常适合动态变化的存储需求。

PV、VG、LV是什么

lv：logical volume LVM的底层单位，实际的物理存储设备或分区

vg：volume group将多个pv聚合在一起，形成一个存储池

pv：physical volume 从vg中分配可用存储空间，格式化后可以使用

physical volume

volume group

logical volume

mount

总结

create PV — pvcreate

create VG — vgcreate

create LV — lvcreate

create a filesystem — mkdf.*

mkdir， mount volume and use

understanding snapshot

理解snapshot之前，得先了解logical volume 是如何存储数据的

logical volume由两个基本部分组成

metadata pointers

data block

创建snapshot时，lvm只需要创建lv的metadata poniter 的副本

lvm snapshot example

流程：

创建一个physical volume pv1

创建一个volume group vp1

创建一个logical volume lv1

初始化lv1文件系统

mount 某个路径到lv1

向lv1文件系统写入一些数据

给lv1创建 snapshot

删除lv1文件系统中的数据

利用snapshot 恢复数据

将snapshot的lv_snap 合并到lv1中
unmount 之前的路径
重新激活lv1
再次mount，可以发现之前已删除数据已经恢复

ref

在linux中，通过lvm来创建pv、gv和lv；快照创建和恢复教程

LVM backup and restore snapshot in Linux

Logical Volume Manager (LVM) is used on Linux to manage hard drives and other storage devices. As the name implies, it can sort raw storage into logical volumes, making it easy to configure and use.

https://linuxconfig.org/create-and-restore-manual-logical-volume-snapshots

k8s从1.20以后开始支持从snapshot导数据进一个新的pvc中

Persistent Volumes

This document describes persistent volumes in Kubernetes. Familiarity with volumes, StorageClasses and VolumeAttributesClasses is suggested. Introduction Managing storage is a distinct problem from managing compute instances. The PersistentVolume subsystem provides an API for users and administrators that abstracts details of how storage is provided from how it is consumed. To do this, we introduce two new API resources: PersistentVolume and PersistentVolumeClaim. A PersistentVolume (PV) is a piece of storage in the cluster that has been provisioned by an administrator or dynamically provisioned using Storage Classes.

https://kubernetes.io/docs/concepts/storage/persistent-volumes/#volume-snapshot-and-restore-volume-from-snapshot-support

lvm对于snapshot 的支持

youtube lvm 讲解

Logical Volume Manager (LVM) - basics tutorial

Linux Command Line tutorial for forensics - 35 - Logical Volume Manager ♥️ SUBSCRIBE for more videos: https://www.youtube.com/bluemonkey4n6?sub_confirmation=1 Difficulty Level: advanced Prerequisites: strong understanding of linux command line strong understanding of partitions and file systems In this video, we will look at the logical volume manager that help you get the most out of disk space. Video timeline 00:00 intro 03:16 Physical Volumes 05:46 Volume Groups 07:36 Logical Volumes 10:44 LVM setup ⭕️ For other videos about the Linux command line, see other videos in this series: https://www.youtube.com/playlist?list=PLSbhiuoC0XgX70ZtgJ7d-1rLui0jZRabg Linux distro: CAINE linux (http://www.caine-live.net) Virtualization software: Virtual Box (http://virtualbox.org) Icons made by freepik from @flaticon http://www.flaticon.com/authors/freepik Icons made by Smashicons from ttp://www.flaticon.com/authors/smashicons This course was designed to provide information on how to use the command line environment in a Unix/Linux system to accomplish tasks such as imaging, data acquisition, and archiving. his course covers the basics of Unix/Linux commands that allow users to view and edit text files, obtain hardware and system information, partitioning and formatting, process related commands, manipulating disks and partitions, imaging, archiving, logical acquisition, live system response, and basic networking. This would be beneficial for folks who are interested in #digitalforensics, #incidenceresponse, system administration, ethical hacking, or just plain linux. his course covers material for beginners as well as for advanced users. This course would also be helpful if you are considering taking the CompTIA Linux+ certification test. #DFIR #Linux #LVM

https://www.youtube.com/watch?v=JlWiNnuMm_4

Logical Volume Manager (LVM) - creating and restoring snapshots

Linux Command Line tutorial for forensics - 37 - Logical Volume Manager - creating and restoring snapshots ♥️ SUBSCRIBE for more videos: https://www.youtube.com/bluemonkey4n6?sub_confirmation=1 Difficulty Level: advanced Prerequisites: strong understanding of linux command line strong understanding of partitions and file systems basic understanding of LVMs (https://www.youtube.com/watch?v=JlWiNnuMm_4) In this video, we will look at creating and restoring snapshots with the logical volume manager. Video timeline 00:00 intro 01:19 Creating snapshots 05:56 Viewing snapshot 07:07 Modifying the original logical volume 07:50 Restoring snapshots ⭕️ For other videos about the Linux command line, see other videos in this series: https://www.youtube.com/playlist?list=PLSbhiuoC0XgX70ZtgJ7d-1rLui0jZRabg Linux distro: CAINE linux (http://www.caine-live.net) Virtualization software: Virtual Box (http://virtualbox.org) Icons made by freepik from @flaticon http://www.flaticon.com/authors/freepik Icons made by Smashicons from ttp://www.flaticon.com/authors/smashicons This course was designed to provide information on how to use the command line environment in a Unix/Linux system to accomplish tasks such as imaging, data acquisition, and archiving. his course covers the basics of Unix/Linux commands that allow users to view and edit text files, obtain hardware and system information, partitioning and formatting, process related commands, manipulating disks and partitions, imaging, archiving, logical acquisition, live system response, and basic networking. This would be beneficial for folks who are interested in #digitalforensics, #incidenceresponse, system administration, ethical hacking, or just plain linux. his course covers material for beginners as well as for advanced users. This course would also be helpful if you are considering taking the CompTIA Linux+ certification test. #DFIR #Linux #LVM

https://www.youtube.com/watch?v=n6cFoPTDHic

🚤LVM