From owner-freebsd-questions Mon Dec 14 07:08:27 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id HAA01354 for freebsd-questions-outgoing; Mon, 14 Dec 1998 07:08:27 -0800 (PST) (envelope-from owner-freebsd-questions@FreeBSD.ORG) Received: from igw3.watson.ibm.com (igw3.watson.ibm.com [198.81.209.18]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id HAA01345 for ; Mon, 14 Dec 1998 07:08:24 -0800 (PST) (envelope-from ribo@watson.ibm.com) Received: from mailhub1.watson.ibm.com (mailhub1.watson.ibm.com [9.2.249.31]) by igw3.watson.ibm.com (8.8.7/07-11-97) with ESMTP id KAA08778 for ; Mon, 14 Dec 1998 10:08:20 -0500 Received: from ribox.watson.ibm.com (ribox.watson.ibm.com [9.2.24.24]) by mailhub1.watson.ibm.com (8.8.7/Feb-20-98) with SMTP id KAA11696 for ; Mon, 14 Dec 1998 10:08:19 -0500 Received: from zap.watson.ibm.com by ribox.watson.ibm.com (AIX 4.1/UCB 5.64/4.03) id AA16874; Mon, 14 Dec 1998 10:03:47 -0500 Message-Id: <3.0.6.32.19981214100216.02269d40@ribox.watson.ibm.com> X-Sender: ribo@ribox.watson.ibm.com (Unverified) X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.6 (32) Date: Mon, 14 Dec 1998 10:02:16 -0500 To: freebsd-questions@FreeBSD.ORG From: Bob Flavin Subject: Boot process and how disk partitions are named Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG I need documentation on the boot process, specifically, how BIOS/FreeBSD assign devices names to SCSI disks (from 3 SCSI channels on 2 SCSI adapters) and which one gets booted and where the kernel is loaded from and what is the order of execution of code through running the /etc/rc files. I couldn't find where stuff like how the mapping of SCSI adapters and devices and FDISK partitions to /dev/sd0s1a or /dev/sd2 or /dev/sd2s1 etc gets done. I assumed that sd1 would refer to the second SCSI controller (even though it has two SCSI channels on it). Would sd1s2 refer to the second hard disk on the second SCSI adapter? Does sd1s2b refer to the second FDISK partition (meaning also the second filesystem) on that second controller and second disk? Given all that, what is the algorithm and process used to boot? BIOS seems to start booting from the designated disk on the LAST SCSI controller found (in this case a PCI card rather than the first SCSI, which is on the motherboard). FreeBSD seems to call this disk something like sd2. But when FreeBSD (probably the boot manager) gets control, it seems to boot the operating system off sd0. Does that boot manager look for the 'boot' flag in FDISK? Bob To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message