Date: Wed, 4 Aug 1999 08:10:18 -0400 (EDT) From: Alfred Perlstein <bright@rush.net> To: jakob@ostenfeld.dk Cc: freebsd-questions@FreeBSD.ORG Subject: Re: Vinum boot support Message-ID: <Pine.BSF.3.96.990804080056.20420z-100000@cygnus.rush.net> In-Reply-To: <19990803231512.A30831@ostenfeld.dk>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, 3 Aug 1999 jakob@ostenfeld.dk wrote:
>
> Hi BSD'ers !
>
> I'm in need of some help or suggestions regarding a setup
> with FreeBSD on a machine with two IDE disks.
>
> I want to run RAID-1 on those disks, and I'm pretty sure I
> can do that with Vinum. However, it's not clear to me whether
> I can make the system boot on the logical RAID-1 volume.
>
> Is it possible ? How ?
>
> The Vinum docs say it's not recommended to have Vinum directly
> in the kernel (it should instead be a loadable module). Now, I
> would expect that this means that I cannot boot on a Vinum
> volume. Why isn't it recommended ?
there isn't enough smarts in the loader to boot from a raid
filesystem, my recommeneded workaround is this:
.----------. .----------.
| root | | backup / |
|----------| |----------|
| | | |
| vinum |
| | | |
|__________| |__________|
another option is using a boot floppy or another workaround
to fetch a kernel off of a non-vinum drive so it can boot.
maybe a floppy drive? or a spare partition on one of the disks...
(vinum would have to be statically compiled in)
> I have a final question with which I do not intend to start
> a flame war... How can I expect FreeBSD disk I/O performance
> to compare to Linux disk I/O performance ? Especially with
> regards to stat() and fsync() ? (I will be running a mail-server
> with ./Maildir/ support)
FreeBSD's I/O subsystem is very good, there operations are more
likely to be limited by available memory (stat) and disk speed (fsync)
than the difference between FreeBSD/Linux.
FreeBSD does have softupdates available, it's a way to run your
disk system in "async" mode (directory operations are async)
in a relatively safe manner.
-Alfred Perlstein - [bright@rush.net|bright@wintelcom.net]
systems administrator and programmer
Wintelcom - http://www.wintelcom.net/
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-questions" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.3.96.990804080056.20420z-100000>