Date: Sat, 23 Jan 1999 11:54:46 +1030 From: Greg Lehey <grog@lemis.com> To: Mark Conway Wirt <mark@intrepid.net> Cc: freebsd-isp@FreeBSD.ORG Subject: ccd and vinum (was: Introduction/ccd(4) Question) Message-ID: <19990123115446.A26886@freebie.lemis.com> In-Reply-To: <19990122200141.A4461@intrepid.net>; from Mark Conway Wirt on Fri, Jan 22, 1999 at 08:01:41PM -0500 References: <19990122200141.A4461@intrepid.net>
next in thread | previous in thread | raw e-mail | index | archive | help
On Friday, 22 January 1999 at 20:01:41 -0500, Mark Conway Wirt wrote: > Traditionally, we've run -- shall we say -- "monolithic" servers, i.e. > $10,000, fully RAID-mirrored big servers for high availability. Of > course we'll continue to do so for mission critical applications like > mail, but I'm also considering putting together some mid-ranged > machines for other purposes. For example, we have some customers who > have expressed interest in on-line commerce, so I'd like to put a > dedicated https server together, but I can't justify spending big > bucks until I know that it can generate revenue. > > Enter ccd. ccd is on its way out, not in. > Granted if a disk fails you'll have some down-time as you swap in > new drives a rebuild the mirrors, but at least it's minimal and you > have much less chance of loosing data than say from restoring from > tape. In the cases I've seen, you need to reboot the machine, reconfigure ccd, recover manually, reconfigure ccd, possibly reboot, and then you're back up and running again. > I have a few questions about ccd though: > > 1) Are any of you ISP's using it, and it it stable? I don't use it, but I believe it's relatively stable. > 2) I assume that the root partition can't be ccd. Correct? and Correct. > 3) If a disk in a mirror set fails, does the ccd fail immediately, > or can you unmount the device and rebuild gracefully? ccd fails immediately. On the other hand, vinum does the right thing: if a drive fails, it will carry on running, and you can rebuild the volumes on line. Take a look at http://www.lemis.com/vinum.html. Greg -- See complete headers for address, home page and phone numbers finger grog@lemis.com for PGP public key To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-isp" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?19990123115446.A26886>