From owner-freebsd-current@FreeBSD.ORG Fri Jan 22 18:34:34 2010 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0A0C51065670; Fri, 22 Jan 2010 18:34:34 +0000 (UTC) (envelope-from fjwcash@gmail.com) Received: from mail-iw0-f177.google.com (mail-iw0-f177.google.com [209.85.223.177]) by mx1.freebsd.org (Postfix) with ESMTP id B4DC68FC1A; Fri, 22 Jan 2010 18:34:33 +0000 (UTC) Received: by iwn7 with SMTP id 7so1197277iwn.7 for ; Fri, 22 Jan 2010 10:34:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type; bh=4yu3IosZGCCIgPv3rz0snaGgWWkc5VLfzSxNfuW1/5k=; b=QySIfm0zmq0tbjSUrchnCGWMoUI2EymH6lcgxp8H9HRVIFgNBvMHGBDl647JseJMoj kWcEIKup+glZ4QGKbak8nuDlVw8L/OBvvsoJNcM8o7/0m8WHwy3BO33VI8Dr09j2p42X irWPvKB/BSPi+VPjY7Z+GJVrIYZwjUCJGHBNY= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=A5tGzjCBQkkJhbAOiwYgAfcsEtXjEDUMYo/fqqdU0m7ls1HOiYz3W+sCNk3cWmJi1s yhdb7za4zH/I7SpDcmaKiYW1kYOE4M1BpM+yGmtJMrIVKOwGKXlvYwt9+rTO0IzYqGsQ Jas9IVWZDn7cbEnwhox3WiuRVZJsZAvtpntzs= MIME-Version: 1.0 Received: by 10.231.170.14 with SMTP id b14mr5392347ibz.26.1264185271378; Fri, 22 Jan 2010 10:34:31 -0800 (PST) In-Reply-To: <4B59EE52.8050400@comcast.net> References: <4B55D9D4.1000008@FreeBSD.org> <4B597CBB.5040900@omnilan.de> <4B59EE52.8050400@comcast.net> Date: Fri, 22 Jan 2010 10:34:31 -0800 Message-ID: From: Freddie Cash To: FreeBSD-Current , FreeBSD Stable Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: Subject: Re: Pack of CAM improvements X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 22 Jan 2010 18:34:34 -0000 On Fri, Jan 22, 2010 at 10:28 AM, Steve Polyack wrote: > On 01/22/10 11:48, Freddie Cash wrote: > >> In my testing of pulling drives at random (using a 3Ware 9550SXU or 9650SE >>> >>> >> controller), you have to "zpool offline " while the drive >> is >> unplugged, before you can re-insert the same disk or a different disk. >> Without doing that step, it's very hard to re-insert the same disk, or >> replace it with a new one, without rebooting. >> >> Took me a couple of reboots and drive replacements before I figured that >> one >> out. :) >> >> > I think you can do it without the 'zpool offline ' command; > I may be wrong, but I believe you can use 'zpool replace' to accomplish > what you're trying to do. i.e. if you have a bad drive ada3, and take it > out, then replace it with a new disk, you can issue a 'zpool replace > /dev/ada3 /dev/ada3' (yes, the same device is specified twice). ZFS should > recognize that its a different disk and/or that it is lacking ZFS metadata > and begin to resilver the pool onto the new device. If you watch 'zfs > status' in the process you'll see something like: > > Yes, that does work ... but it's not nearly as reliable as doing the offline first. If you do things in the right order, drives can be replaced and resilvering started within minutes (our process takes a little less than 5 minutes, but the bulk of that is removing the dead drive from the caddy, and adding the new drive to the caddy). Do things in the wrong order, and it can take 15 minutes or more, and may require rebooting the system (as our manager discovered trying to replace a drive while I was away). :) Just because there are shortcuts available ... doesn't mean you should always take them. :D -- Freddie Cash fjwcash@gmail.com