From owner-freebsd-stable Mon Mar 10 6:24:18 2003 Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 1103437B401 for ; Mon, 10 Mar 2003 06:24:17 -0800 (PST) Received: from whizzo.transsys.com (whizzo.TransSys.COM [144.202.42.10]) by mx1.FreeBSD.org (Postfix) with ESMTP id 6C05143FB1 for ; Mon, 10 Mar 2003 06:24:16 -0800 (PST) (envelope-from louie@whizzo.transsys.com) Received: from whizzo.transsys.com (#6@localhost [127.0.0.1]) by whizzo.transsys.com (8.12.8/8.12.7) with ESMTP id h2AEOFQp038066 for ; Mon, 10 Mar 2003 09:24:16 -0500 (EST) (envelope-from louie@whizzo.transsys.com) Message-Id: <200303101424.h2AEOFQp038066@whizzo.transsys.com> X-Mailer: exmh version 2.5 07/13/2001 with nmh-1.0.4 X-Image-URL: http://www.transsys.com/louie/images/louie-mail.jpg To: stable@freebsd.org From: "Louis A. Mamakos" Subject: USB storage devices and booting Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Mon, 10 Mar 2003 09:24:15 -0500 Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG While testing a fix to a USB driver a little while ago, I ran into a weird but explainable situation. Say, for example, you've got a FreeBSD system with one or more SCSI disks, and with the root partition on one of those disks. The loader passes along a hint as to which device the kernel should mount as the root partition, and away we go. Now, boot your system with a USB storage device attached. It seems to get bound as "da0" before the first SCSI drive has a chance to. This results in surprising behavior when you boot and it can't mount a root partition off the drive it thought it booted from. I suppose I could hardwire the SCSI drives in my kernel configuration, but that doesn't seem like the right answer. I don't normally boot with the USB storage thing plugged in, but it's possible that I might leave one attached and then have the system reboot while it's unattended and not come back. Is there a relative priority between the various drivers as they get device names allocated from (presumably) the CAM subsystem? louie To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message