Growing a RAID-5 volume with Veritas Volume Manager

Growing a RAID-5 volume with Veritas Volume Manager

Post by Mike Frampto » Mon, 09 Jun 1997 04:00:00



Hello all,

What's the simplest way to grow an existing RAID-5 volume with VxVM. In
the past I have been stripping and mirroring my 20 plus GB volume, which
means a complete rebuild and restore if I want to grow these file
systems.

Is there a way of concatenating RAID-5 volume together?

Many thanks,

Koon Tang

 
 
 

Growing a RAID-5 volume with Veritas Volume Manager

Post by Doug Hugh » Tue, 10 Jun 1997 04:00:00



> Hello all,

> What's the simplest way to grow an existing RAID-5 volume with VxVM. In
> the past I have been stripping and mirroring my 20 plus GB volume, which
> means a complete rebuild and restore if I want to grow these file
> systems.

Let's assume you have an existing RAID-5 volume over 6 disks (not necessarily
the whole disk) in your storage array. The best way is to grow all the
subdisks in place. This may be done by rearranging your existing subdisks,
or if there is nothing after (physically on the disk) your existing subdisks,
you can grow there.

 The easiest way would probably be to pick 6 new disks (if you have a 5
disk RAID-5 volume, pick 5 new disks)..

 In between would be to use the same disks as in the first option, but have
the space allocated noncontiguously. This won't phase VxVM (we've done it)
but it will look kind of ugly and might be confusing to somebody later on.
Keeping it simpler is preferable.

 The main point is that you need to pick as many new disks/subdisks as you have
disks in your current stripe to grow your volume (excluding the log subdisk).

 There is a mail-list devoted specifically to issues of SparcStorage
Array management (be it Veritas VxVM, or Sun ODS). To subscribe send

words 'susbcribe ssa-managers'

--
____________________________________________________________________________
Doug Hughes                                     Engineering Network Services
System/Net Admin                                Auburn University


 
 
 

Growing a RAID-5 volume with Veritas Volume Manager

Post by Stefan Kwiatkowsk » Tue, 10 Jun 1997 04:00:00



> What's the simplest way to grow an existing RAID-5 volume with VxVM. In
> the past I have been stripping and mirroring my 20 plus GB volume, which
> means a complete rebuild and restore if I want to grow these file
> systems.

First, you will need to work within the context of a diskgroup...

You will need available subdisks from within your diskgroup (of which
your
existing RAID5 set is a member). The subdisks should be on separate
disks.
You can do this while your RAID5 filesystem is mounted:
  1) Add a new drive(s) into your diskgroup
  2) Make subdisks as needed    
  3) Click on a free subdisk (lets say its 100MB) and drag it onto the
RAID5 plex
  4) Click on the RAID5 icon so as to highlight it      
  5) Click on Basic-ops|File System|Resize and grow by the amount that
you have
     available in the new subdisk
  6) Done

Quote:> Is there a way of concatenating RAID-5 volume together?

  By its nature, the RAID5 will not physically concatenate data space
but with rather
  add to the plex. Try not to go over 6-7 disks if you want to maintain
performance.

--

----------------------------
Stefan Kwiatkowski

Open Systems Engineering Manager
Bay State Computer Group
http://www.bscg.com
908-417-1122 x221