LinuxQuestions.org
Welcome to the most active Linux Forum on the web.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Server
User Name
Password
Linux - Server This forum is for the discussion of Linux Software used in a server related context.

Notices


Reply
  Search this Thread
Old 02-04-2010, 06:48 AM   #1
batfastad
Member
 
Registered: Nov 2004
Location: London, UK
Distribution: CentOS, RHEL, Debian, IPCop, PS2Linux
Posts: 95

Rep: Reputation: 23
CentOS install onto software RAID 10


Hi everyone
Just a quick one really.

Planning a new server install (to eventually run Zimbra) and I'll be going with CentOS since our file server and intranet servers both run it as well.
The server will only be serving 10-15 users so I've gone for plain old 500GB SATA drives and I'm planning to put 4 of these in a RAID 10 (we have 4 spare after recently upgrading our file server).

I've never experimented with Linux software RAID before but it seems like its been around a while and I've read other people using it on a day to day basis.
For this server I thought I could get away with software RAID 10 since it should be less demanding on the CPU compared to RAID 5/6.
And I'd like the improved performance that RAID 10 offers over a plain RAID 1 mirror.

It seems relatively easy to set up under CentOS as there's software RAID options during the install process but one thing I did read is that the /boot partition has to be installed on a RAID 1

So how about this for a plan:
Create 4x 200MB software RAID partitions (one per drive) then configure them in a RAID 1 for /boot
Then 4 other software RAID partitions (one per drive) using the remaining space for the RAID 10

But then what do I do about swap?
Any other comments/suggestions on this?

Is it actually possible to boot from a Linux software RAID?

Cheers, B
 
Old 02-04-2010, 03:49 PM   #2
kbp
Senior Member
 
Registered: Aug 2009
Posts: 3,790

Rep: Reputation: 653Reputation: 653Reputation: 653Reputation: 653Reputation: 653Reputation: 653
Have you thought about using a SATA raid card ?... then you can choose a raid format that works for you data-wise rather than worrying about cpu usage.

Yes, you can boot off software raid ( at least raid 1 that I'm aware of )

cheers
 
Old 02-04-2010, 04:46 PM   #3
batfastad
Member
 
Registered: Nov 2004
Location: London, UK
Distribution: CentOS, RHEL, Debian, IPCop, PS2Linux
Posts: 95

Original Poster
Rep: Reputation: 23
Question

Yeah thought about hardware RAID. We actually use a 3Ware 9690SA-8i in our file server with 8x1TB drives in a RAID 6.
But I was under the impression that RAID 5/6 need significantly more oomph than RAID 0/1/10 because of the added parity calculations.

Ideally I would go hardware RAID but the CPU in this new box is a quad-core Xeon X3360 so I think it's got more than enough grunt to handle RAID 10.

I did think I'd need to make a RAID 1 for the /boot partition then the rest of / can sit on a RAID 10.

My main question was the stability of software RAID, is it still experimental or would running a software RAID 10 be fine?

Also what do I do about the swap partition in the CentOS installer?

Cheers, B
 
Old 02-04-2010, 05:38 PM   #4
kbp
Senior Member
 
Registered: Aug 2009
Posts: 3,790

Rep: Reputation: 653Reputation: 653Reputation: 653Reputation: 653Reputation: 653Reputation: 653
Personally I use hardware raid every time, but lots of people use software raid and it is fairly mature.

Regarding the swap partition - I wouldn't worry too much unless you happen to be running some memory intensive applications, linux usually won't touch swap much unless it's running out of physical memory.

( when I say "dont worry", I mean about location, you do still need swap )

Last edited by kbp; 02-04-2010 at 05:42 PM.
 
Old 02-04-2010, 07:28 PM   #5
chrism01
LQ Guru
 
Registered: Aug 2004
Location: Sydney
Distribution: Rocky 9.2
Posts: 18,344

Rep: Reputation: 2746Reputation: 2746Reputation: 2746Reputation: 2746Reputation: 2746Reputation: 2746Reputation: 2746Reputation: 2746Reputation: 2746Reputation: 2746Reputation: 2746
Just to clarify, its not that /boot has to be installed on RAID1, its just that if you want to RAID /boot, RAID1 is the only option (just in case anyone wondered).
Linux SW raid is pretty mature.
Given swap is only used as temp workspace when the kernel runs out of RAM, I probably wouldn't bother raiding it.
You might want to have 2 swap partitions (separate disks) to minimise downtime if 1st one goes bad.
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
Recovering the OS from software RAID HDD crash with rPath (or RHEL/CentOS/Fedora)? pwjohnston Linux - Server 0 08-21-2009 08:01 PM
Centos kernel upgrade breaks dmraid on Intel Software Raid JevidL Linux - Kernel 9 06-08-2009 05:30 AM
Installing CentOS 5.1 onto a software raid 1+0 configW alfista Linux - Server 3 03-10-2008 10:03 PM
Software RAID 1 setup on CentOS using Grub boot loader kumarsundaram Linux - Software 1 11-30-2005 12:57 PM
Installing Debian after CentOS with software RAID arsham Linux - Distributions 0 11-07-2005 05:12 AM

LinuxQuestions.org > Forums > Linux Forums > Linux - Server

All times are GMT -5. The time now is 01:00 AM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration