Difference between revisions of "Software RAID"

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(→‎Reasons: SoftwareRaid1 Howto on Singlehost by Oerb)
 
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We do not support '''Software RAID (mdraid)''' in offical Proxmox kernel.
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== Introduction ==
  
== Reasons ==
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Software RAID is an alternative for using hardware-RAID controller for local storage.
The basic reason is that proxmox.com want to offer support for their system, and software raid would cause unjustified burden for us.
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Please note that Proxmox VE currently only supports one technology for local software defined RAID storage: ZFS
  
The problems are:
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== Supported Technologies ==
# Most system admins are unable to recover from a software raid error because they never read the documentation.
 
# RAID1 is not the onyl raid level - I we want to fully support software raid we need a quite complex interface to configure that (RAID5, RAID10, ..)
 
# We want to use LVM2 (snapshots). This adds an additional level of complexity, i.e. if you recover or if you want to extend your system by adding harddisks.
 
# One single failed disk can make the whole system unusable - we observed this with sotware raid - but never with hardware raid
 
  
* The developers know that Proxmox VE will not work with soft raid [http://www.proxmox.com/forum/showpost.php?p=4406&postcount=3]
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=== ZFS ===
* It creates problems in proxmox special setup
 
* May stop working after an upgrade
 
  
See also forum: http://www.proxmox.com/forum/showthread.php?t=398
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If you want to run a supported configuration, using a proven enterprise storage technology, with data integrity checks and auto-repair capabilities ZFS is the right choice.
== Comunity ==
 
  
A German introduction to a Software Raid1. It just works on a single Host without Clustersupport. [http://oerb.de/index.php?option=com_content&view=article&id=66:proxmox-ve-mit-raid-howto&catid=22:administration&Itemid=12]
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See the [[ZFS on Linux]] article for more information.
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== Unsupported Technologies ==
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=== btrfs ===
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btrfs can actually be a very safe and functional choice, but it is not yet supported by Proxmox VE. It will be re-evaluated for Proxmox VE 7.0.
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=== mdraid ===
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mdraid has zero checks for bitrot, data integrity, and most filesystems on top do not provide that either.
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That means, if some data gets corrupted, which happens on any long-running system sooner or later, and you normally do not notice until it's too late.
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So, Proxmox projects do '''not''' support it to avoid that users run into these problems!
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For non-production/unsupported setups, where you still want to use mdraid (please don't!), you can create the required RAID level during Debian installation and then install Proxmox VE or create RAID after install Proxmox VE.
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Look at the following pages:
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* Debian 9 - [[Install Proxmox VE on Debian Stretch]]
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* Debian 10 - [[Install Proxmox VE on Debian Buster]]
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If you need further assistance for md-raid, it's another good sign that you do not want to choose that technology.
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[[Category: HOWTO]]

Latest revision as of 09:29, 29 March 2021

Introduction

Software RAID is an alternative for using hardware-RAID controller for local storage. Please note that Proxmox VE currently only supports one technology for local software defined RAID storage: ZFS

Supported Technologies

ZFS

If you want to run a supported configuration, using a proven enterprise storage technology, with data integrity checks and auto-repair capabilities ZFS is the right choice.

See the ZFS on Linux article for more information.

Unsupported Technologies

btrfs

btrfs can actually be a very safe and functional choice, but it is not yet supported by Proxmox VE. It will be re-evaluated for Proxmox VE 7.0.

mdraid

mdraid has zero checks for bitrot, data integrity, and most filesystems on top do not provide that either.

That means, if some data gets corrupted, which happens on any long-running system sooner or later, and you normally do not notice until it's too late. So, Proxmox projects do not support it to avoid that users run into these problems!

For non-production/unsupported setups, where you still want to use mdraid (please don't!), you can create the required RAID level during Debian installation and then install Proxmox VE or create RAID after install Proxmox VE. Look at the following pages:

If you need further assistance for md-raid, it's another good sign that you do not want to choose that technology.