HDD Partitioning and pool management

Issues related to hardware problems
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SecCon
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HDD Partitioning and pool management

Post by SecCon » 2020/11/05 09:57:44

Can someone point me to a guide where I could get more info on handling drives, filesystems and partitioning in order to get the into storage pools for VM usage? I know the basics, done it for many years in Windows, but right now I have one drive formatted as ZFS and another as XFS on two servers and I really don't know how that happened in the first place. Those are supposed to be identical volumes and storage pools.

I guess I need to remake this in Terminal some how but I have no clue as to how. The tool I used to create this in the first place was the Storage plugin for Cockpit, but it does not seem to do the same, despite identical hardware.

These are NOT the system drive on sda so that is not in jeopardy...its a raid5 with 6.5TB on /sdb
Windows SysOp - Linux wannabe > CentOS newb.

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jlehtone
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Re: HDD Partitioning and pool management

Post by jlehtone » 2020/11/05 10:33:20

ZFS is not supported by base CentOS, AFAIK. To have ZFS means that someone/something has installed and used tools from third-party repositories.
A simple "I did click a button" should not achieve that. If it does, then I'm genuinely scared.


"storage pools for VM usage"

The libvirtd.service that is the default solution for VM management in CentOS does support many storage back-ends. One of them does use LVM.

With LVM you have a partition on a disk. A LVM Physical Volume (PV) in a partition. The PV is part of Volume Group (VG) and the VG has one or more Logical Volumes (LV).

An LV can have a filesystem that is then mounted somewhere. However, LV without filesystem can be given to a VM, which sees it as "a disk" and is free to partition and use the "disk" as it pleases.

Another back-end are files. The host has a mounted filesystem and libvirtd creates a file that the VM will see as "a disk".



RAID5. You do know the odds that large disks have, don't you?

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SecCon
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Re: HDD Partitioning and pool management

Post by SecCon » 2020/11/05 11:07:08

What scares ME is the gazillion ways you can do this in different Linux based systems. The logic is basically the same, but there are no standards on how to do it...as in the interface..

Right now i am like three seconds from throwing this shit out and do HyperV in Windows Server jeez...
Windows SysOp - Linux wannabe > CentOS newb.

BShT
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Re: HDD Partitioning and pool management

Post by BShT » 2020/11/05 11:35:24

you are exposed to a layer down

you are scarred because you have to control what you don´t know

it is normal to feel that way, Jon "Maddog" Hall call it once "break the magic layer" and learn how things really works

welcome to the matrix, you can choose the red pill or not...

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jlehtone
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Re: HDD Partitioning and pool management

Post by jlehtone » 2020/11/05 11:57:45

SecCon wrote:
2020/11/05 11:07:08
What scares ME is the gazillion ways you can do this in different Linux based systems.
Open source people tend to emphasize that you can do. The downside is that one has to do an informed choice.

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SecCon
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Re: HDD Partitioning and pool management

Post by SecCon » 2020/11/05 12:41:37

BShT wrote:
2020/11/05 11:35:24
you are exposed to a layer down

you are scarred because you have to control what you don´t know

it is normal to feel that way, Jon "Maddog" Hall call it once "break the magic layer" and learn how things really works

welcome to the matrix, you can choose the red pill or not...
Gimme the BLUE pill....
jlehtone wrote:
2020/11/05 11:57:45
SecCon wrote:
2020/11/05 11:07:08
What scares ME is the gazillion ways you can do this in different Linux based systems.
Open source people tend to emphasize that you can do. The downside is that one has to do an informed choice.
If I were to learn stuff from scratch every time i try a new OS, only because they apply the same logic in a different way and call sda c: or c: sda... I am too old for this.. I started with wanting to sync images from an iphone to a local share using nextcloud, several weeks later I am still struggling to get the basic stuff running... :shock:
Windows SysOp - Linux wannabe > CentOS newb.

BShT
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Re: HDD Partitioning and pool management

Post by BShT » 2020/11/05 13:03:02

most of Unix are more or less the same

even if you have a Unix inside a lollypop like MacOS or Android

never use graphical tools and you will see that you can manage CentOS as Debian as FreeBSD

you can feel the noobness of an admin that install a GUI

GUIs are for users

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jlehtone
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Re: HDD Partitioning and pool management

Post by jlehtone » 2020/11/05 13:51:19

SecCon wrote:
2020/11/05 12:41:37
If I were to learn stuff from scratch every time i try a new OS
There are multiple levels. Principles/ideology are mostly agnostic about OS. Implementation details are more specific.

Same applies to programming languages. Abstract concepts of data and instructions apply to all. Then there are large families, like procedural and functional, and finally there is specific syntax of each language.

The "everything is a file and all files are in a tree with one root" of Unix is used in to most OS.

Technically, partition != filesystem. Not even in Windows. It is the UI (and limited documentation) that hides the details behind abstract "format a partition" action.

The partition table format used by MS-DOS (and Linux too) on "PC" hardware (legacy BIOS) had strict limitations and hard drives were small.
LVM (Logical Volume Manager) is one workaround for those challenges. I'm sure that Windows has something similar.

bspeedtriple
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Re: HDD Partitioning and pool management

Post by bspeedtriple » 2020/11/05 15:08:02

Without wanting to start a religious war on windows/Linux/Unix and filesystems to choose from I would like to come back on :

>>>
If I were to learn stuff from scratch every time i try a new OS, only because they apply the same logic in a different way and call sda c: or c: sda... I am too old for this.. I started with wanting to sync images from an iphone to a local share using nextcloud, several weeks later I am still struggling to get the basic stuff running... <<<<

If you are experienced with Windows why not setup Nextcloud on Windows, learning the pro's and cons of a new OS is always a challenge. If you like to learn a new system then be prepared, beside setting up disks and filesystems you have to install a database, webserver and the nextcloud application from the command prompt.

My nextcloud is running on an CentOS 8 system without a graphical user interface and beside downtime due system updates it is running 24/7.

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SecCon
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Re: HDD Partitioning and pool management

Post by SecCon » 2020/11/05 17:55:22

BShT wrote:
2020/11/05 13:03:02
never use graphical tools and you will see that you can manage CentOS as Debian as FreeBSD

you can feel the noobness of an admin that install a GUI

GUIs are for users
I hate CLI. This is not 1984 any more. But I will admit it is many times more useful.
bspeedtriple wrote:
2020/11/05 15:08:02
If you are experienced with Windows why not setup Nextcloud on Windows, learning the pro's and cons of a new OS is always a challenge. If you like to learn a new system then be prepared, beside setting up disks and filesystems you have to install a database, webserver and the nextcloud application from the command prompt.
Because I strive to remain legal with long term projects. Windows Server will legally cost me way more than the time i spend learn this, but I am beginning to doubt that...
Windows SysOp - Linux wannabe > CentOS newb.

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