From owner-freebsd-bugs@FreeBSD.ORG Sun Jan 24 11:50:04 2010 Return-Path: Delivered-To: freebsd-bugs@hub.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id BE677106566B for ; Sun, 24 Jan 2010 11:50:04 +0000 (UTC) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (freefall.freebsd.org [IPv6:2001:4f8:fff6::28]) by mx1.freebsd.org (Postfix) with ESMTP id ACE3C8FC15 for ; Sun, 24 Jan 2010 11:50:04 +0000 (UTC) Received: from freefall.freebsd.org (localhost [127.0.0.1]) by freefall.freebsd.org (8.14.3/8.14.3) with ESMTP id o0OBo46d078478 for ; Sun, 24 Jan 2010 11:50:04 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.14.3/8.14.3/Submit) id o0OBo4N2078477; Sun, 24 Jan 2010 11:50:04 GMT (envelope-from gnats) Date: Sun, 24 Jan 2010 11:50:04 GMT Message-Id: <201001241150.o0OBo4N2078477@freefall.freebsd.org> To: freebsd-bugs@FreeBSD.org From: Oles Hnatkevych Cc: Subject: Re: kern/143056: [ata] atacontrol(8) can not create raid1 (mirror) from one drive X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Oles Hnatkevych List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 24 Jan 2010 11:50:04 -0000 The following reply was made to PR kern/143056; it has been noted by GNATS. From: Oles Hnatkevych To: bug-followup@FreeBSD.org, don_oles@able.com.ua Cc: Subject: Re: kern/143056: [ata] atacontrol(8) can not create raid1 (mirror) from one drive Date: Sun, 24 Jan 2010 13:49:13 +0200 Hello! How I can persuade people that there's no anything in any religion against creating degraded mirrors from one hard drive, since it is 1) technically possible 2) it is very helpful Let's change the documentation and fix the religious problem. Example 1: The 300GB mirror is broken on a production system. But the space is scarce, the decision is to migrate to 500 GB mirror. Two 500G disks are bought. Intended (unsupported) way: The 500GB disk is inserted, from it created a one-disk mirror, mirror is sliced and configured to boot, with rsync the whole system is migrated from one degraded mirror to another, then again in single-user mode, server turned off , 300 Gb disk taken out, both 500 Gb disks inserted, server booted from a degraded 500G mirror, second disk added to mirror. The way I had to go: The same but I had to find a separate box in which I inserted both 500G drives, boot from freebsd dvd in fixit mode, create full mirror, take one hard drive, boot again and remove degraded mirror from second hard drive (to add it later, not to confuse the production server). Example 2: I want to have a mirror but right now only one hard drive is available, but I know that in month or two I'll have money to buy another one. It's much more convenient to setup system on one-drive-mirror and then add another one than to mess around with migration from single-drive without mirror to a full mirror. Much more. Gmirror already supports one-drive mirrors. Yes, its author is more open-minded. -- ---------- Oles Hnatkevych Skype: don_oles Email/Jabber: don_oles@able.com.ua http://gnut.able.com.ua/