Date: Thu, 9 Apr 1998 17:13:49 +0930 From: Greg Lehey <grog@lemis.com> To: Greg Pavelcak <gpavelcak@philos.umass.edu>, freebsd-questions@FreeBSD.ORG Subject: Re: Check on ccd setup and "Vinum(??)" question Message-ID: <19980409171349.57448@freebie.lemis.com> In-Reply-To: <0ER4004MBPGTD7@rfd1.oit.umass.edu>; from Greg Pavelcak on Thu, Apr 09, 1998 at 12:24:23AM %2B0000 References: <0ER4004MBPGTD7@rfd1.oit.umass.edu>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, 9 April 1998 at 0:24:23 +0000, Greg Pavelcak wrote:
> I think I'm starting to get ccd, but I just wanted to run this by you
> all before I try it. I don't want to hurt anything.
>
> I have two Maxtor IDE drives: a 3.2G Diamondmax (UltraDMA), and a 2.1G
> CrystalMax (Not UDMA). My controllers don't support UDMA anyway. I just
> want to make sure I can do the following.
>
> Suppose I partition the disks like this.
>
> 3.2G 2.1G
> ---- ----
> 64M swap 64M swap
> 2.1G-64M /usr1 2.1G-64M /usr2
> 64M /
> remainder /usr
>
> The idea, of course, is to get two file systems, /usr1 and /usr2
> that are the same size.
>
> Then I'll do an ordinary install onto / and /usr, ccd /usr1 and /usr2.
> Finally, I'll move the /usr stuff to the ccd and mount it on /usr
> resulting, I hope, in better performance from my disks, and I'll use the
> former /usr partition just for sources and ports distfiles.
>
> Does this make sense?
Up to a point. There are a number of ways to shoot yourself in the
foot. I'm assuming a striped rather than a concatenated organization,
since your goal is performance, not reliability.
1. Make sure you put your / file system up front. There are various
limits that can bite you and stop the system from booting
otherwise. You also probably don't need more than 40 MB / unless
you have some strange things you want to do there.
2. The partitions used by ccd don't have file system names. You
might call them /dev/wd0s1f and /dev/wd1s1f, for example.
3. You don't really need the third /usr file system. You can set ccd
up to run before you go multi-user, so the ccd file systems are
enough.
4. If one of your disks dies, ccd is too stupid to bring up the
remaining one by itself. You'll have to reboot and reconfigure
ccd.
I believe the correct ccdconfig entry for this would be:
ccd0 128 CCDF_UNIFORM /dev/wd0s1f /dev/wd1s1f
In vinum (remember, you read it here first) you would define a file
system like this:
drive a device /dev/wd0s1f
drive b device /dev/wd1s1f
volume usr
plex org striped 64k
subdisk size 64m drive a
subdisk size 64m drive b
Greg
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?19980409171349.57448>