From: Ed W <lists@wildgooses.com>
To: Stan Hoeppner <stan@hardwarefreak.com>
Cc: linux-raid@vger.kernel.org
Subject: Re: HBA Adaptor advice
Date: Sat, 21 May 2011 10:52:30 +0100 [thread overview]
Message-ID: <4DD78B5E.30300@wildgooses.com> (raw)
In-Reply-To: <4DD5FC66.5020209@hardwarefreak.com>
On 20/05/2011 06:30, Stan Hoeppner wrote:
>> Are there actually any HBAs that have BBU without using their RAID
>> features?
>
> AFAIK the LSI real RAID cards allow this. To get them into a JBOD mode
> you have to create a single drive RAID 0 of each disk and export it. By
> doing so the RAID firmware is actually active, though not really doing
> anything, so you get the cache and BBU benefit of the controller. One
> of the XFS developers, Dave Chinner, posted this to the XFS list quite
> some time ago when we discussed hardware vs software RAID setups.
>
Something I didn't consider:
When you setup most hardware raid cards to have a whole bunch of RAID0
arrays (that are then assembled as software raid), *can* I swap that
hardware raid card for a different make/model or even non raid HBA?
If I can't do this then I don't want such a card... The entire point of
avoiding hardware raid was simply to avoid the proprietory lockin...
So, to be specific, given one of the LSI/3Ware/Areca fast hardware raid
cards mentioned in this thread, and assuming that I have created a bunch
of raid0 arrays, each containing 1 drive, can anyone confirm/deny if
those single disks than then be moved to a) non raid HBA controller, b)
another hardware raid controller as a new raid0 array
I'm rather expecting that a) might be possible if the HBA can ignore the
proprietory bit and see a raw partition, but b) seems highly unlikely
since the new controller presumably wants to reformat the array in it's
own format before it will use it?
If neither are possible then there seems little advantage in using a
hardware raid as a write caching HBA card (unless the card is too
underpowered that it's a bottleneck)
Thanks
Ed W
next prev parent reply other threads:[~2011-05-21 9:52 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-19 12:26 HBA Adaptor advice Ed W
2011-05-19 12:36 ` Roman Mamedov
2011-05-19 12:43 ` Mathias Burén
2011-05-19 14:06 ` Michael Sallaway
2011-05-19 19:10 ` Thomas Harold
2011-05-19 21:12 ` Rudy Zijlstra
2011-05-19 21:07 ` Brad Campbell
2011-05-20 20:58 ` Tobias McNulty
2011-05-20 21:23 ` Brad Campbell
2011-05-20 2:08 ` Andy Smith
2011-05-20 5:30 ` Stan Hoeppner
2011-05-21 9:52 ` Ed W [this message]
2011-05-20 7:33 ` Ed W
2011-05-20 10:21 ` Stan Hoeppner
2011-05-21 11:17 ` Ed W
2011-05-21 11:29 ` Rudy Zijlstra
2011-05-21 11:54 ` Ed W
2011-05-21 17:37 ` Leslie Rhorer
2011-05-22 9:41 ` Stan Hoeppner
2011-05-22 10:03 ` Rudy Zijlstra
2011-05-23 9:32 ` Ed W
2011-05-21 17:05 ` Leslie Rhorer
2011-05-22 9:04 ` Stan Hoeppner
2011-05-22 10:09 ` Brad Campbell
2011-05-22 19:25 ` Stan Hoeppner
2011-05-22 20:57 ` Tobias McNulty
2011-05-22 21:13 ` Johannes Truschnigg
2011-05-23 9:48 ` Ed W
2011-05-23 10:44 ` John Robinson
2011-05-22 23:19 ` Brad Campbell
2011-05-23 4:09 ` Roman Mamedov
2011-05-23 5:54 ` Brad Campbell
2011-05-23 6:08 ` Roman Mamedov
2011-05-23 10:42 ` Stan Hoeppner
2011-05-23 11:35 ` David Brown
2011-05-23 6:54 ` Stan Hoeppner
2011-05-23 7:23 ` Brad Campbell
2011-05-22 23:44 ` Brad Campbell
2011-05-23 0:07 ` Brad Campbell
2011-05-23 5:30 ` Stefan /*St0fF*/ Hübner
2011-05-23 10:18 ` Ed W
2011-05-23 9:58 ` Stan Hoeppner
2011-05-23 10:33 ` Ed W
2011-05-23 11:21 ` Stan Hoeppner
2011-05-20 12:18 ` Joe Landman
2011-05-20 12:34 ` Roman Mamedov
2011-05-20 12:36 ` Mathias Burén
2011-05-20 12:48 ` Joe Landman
2011-05-20 13:21 ` Ed W
2011-05-20 14:23 ` Joe Landman
2011-05-20 20:01 ` Andy Smith
2011-05-20 20:12 ` Stan Hoeppner
2011-05-20 20:24 ` Drew
2011-05-20 20:58 ` Stan Hoeppner
[not found] ` <4DD7A100.2010807@wildgooses.com>
2011-05-22 8:13 ` Stan Hoeppner
-- strict thread matches above, loose matches on Subject: below --
2011-05-23 2:11 Jim Schatzman
2011-05-23 3:39 ` Tobias McNulty
2011-05-23 10:42 ` Ed W
2011-05-23 11:14 HBA Adaptor Advice Ed W
2011-05-23 11:55 ` Joe Landman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4DD78B5E.30300@wildgooses.com \
--to=lists@wildgooses.com \
--cc=linux-raid@vger.kernel.org \
--cc=stan@hardwarefreak.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).