LinuxQuestions.org
Latest LQ Deal: Latest LQ Deals
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Hardware
User Name
Password
Linux - Hardware This forum is for Hardware issues.
Having trouble installing a piece of hardware? Want to know if that peripheral is compatible with Linux?

Notices


Reply
  Search this Thread
Old 10-18-2005, 03:09 AM   #1
kheldar
Member
 
Registered: Jul 2004
Location: Nottingham, England
Distribution: Fedora 17, Centos 6.3 x86_64
Posts: 35

Rep: Reputation: 2
Adding additional drives/resizing drives in RAID arrays


Hi,

I've currently got a setup with 4 hdds, of different sizes, raided to provide speed and resiliancy.

I want to upgrade the disks as they are getting full, but I've a significant problem in that I can't backup the drives, and I can't reallisticly add any more quantity of drives.

What I have at present is 2x160gb and 2x80gb. They are arranged as a 4x80 raid 5, and the remainder of the 2x160 are a raid-1.

What I want to achive is replace some or all of the drives with larger ones, without losing any data.

Is it possible with a raid-5 to add additional drives to the array once it's been set up, apart from "spare" devices?

Does anyone have any suggestions as to a suitable migration plan?

Thanks in advance.

Kheldar.
 
Old 10-19-2005, 01:21 PM   #2
ironwalker
Member
 
Registered: Feb 2003
Location: 1st hop-NYC/NewJersey shore,north....2nd hop-upstate....3rd hop-texas...4th hop-southdakota(sturgis)...5th hop-san diego.....6th hop-atlantic ocean! Final hop-resting in dreamland dreamwalking and meeting new people from past lives...gd' night.
Distribution: Siduction, the only way to do Debian Unstable
Posts: 506

Rep: Reputation: Disabled
Mdadm will solve all your problems.The explanations to your questions would be a lot of writeing and you are best to read the mdadm man pages.

Heres a review with some detailed info on some of its features and options.
There are appropriate links to mdadm page in the review.
http://www.linuxdevcenter.com/pub/a/...2/05/RAID.html

http://gd.tuwien.ac.at/linuxcommand....es/mdadm8.html

I have added extra drives to my raid 5 array.It origionally consisted of 4 35 g raptors and I added 3 more.3 was active one was spare...with the 3 new ones I formatted exactly how I had the others formatted(4 partitions) and then added makeing 2 active for a total of 5 and 1 a spare for a total of 2 spares.It wasnt hard.In my case the extra drives was adding free space.The rebuild utilised the free space without disrupting filesystem.

The easiest way is if you have LVM over your raid setup.This allows for an easy transition of growing a filesystem size.

Heres a good howto on manageing raid and lvm
http://home.gagme.com/greg/linux/raid-lvm.php

Also part of the raidtools package,"raidhot[add|remove]" is used to add or remove a disk from a RAID array.

Following are examples of their use:

*

raidhotremove /dev/sda1 /dev/md0 (hot remove the partition /dev/sda1 from /dev/md0)
*

raidhotadd /dev/sda1 /dev/md0 (hot add the partition /dev/sda1 to /dev/md0)


Have a look here,it should give a link to what you need.
http://www.tldp.org/HOWTO/Software-RAID-HOWTO-10.html

The above is the last page to software raid how to and is an excellent guide.

Hope this helps.
 
  


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
Adding additional drive to make a RAID 1 config khooke Linux - Hardware 2 09-25-2005 12:39 AM
adding drives to fstab kurrupt Debian 1 08-09-2004 12:17 AM
Add Additional Hard Drives rawdave Linux - Newbie 3 03-17-2004 09:47 AM
Upgrading hard drives on Software raid 1 boot drives. linuxboy123 Linux - General 0 12-11-2003 03:28 PM
Adding Additional HD With Raid Present LeeForkenbrock Linux - Hardware 2 07-23-2003 04:43 PM

LinuxQuestions.org > Forums > Linux Forums > Linux - Hardware

All times are GMT -5. The time now is 06:21 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