From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Furness Subject: Can I define SCSI device order? Date: 10 Mar 2003 12:52:12 +0000 Sender: linux-admin-owner@vger.kernel.org Message-ID: <1047300731.13910.333.camel@Zebra.vil.ite.mee.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: List-Id: Content-Type: text/plain; charset="us-ascii" To: linux-admin@vger.kernel.org Good morning everyone. I'm building a new system. It's a Dell Poweredge 2650 which has an embedded SCSI controller with 2 HDD's attached. It also has in it an Adaptec 39160 PCI card, which I want to use for external SCSI devices. The plan is: Build the system (installing RedHat 7.3 + patches), and then plug in the external RAID array which presents itself as a single SCSI device. The problem is that when I plug in the external array, it takes over as "sda", shunting the disk with linux on it up to "sdb". This means that it can't find the root partition, so although it starts booting from the right place, it then kernel panics. I _could_ change the configuration of grub and also fstab so that the system boots happily from sdb, but then it is a problem if I remove the disk array. Since there will be a backup system with exactly the same hardware but no array, I need to be able to plug in the array and boot the system without any messing around changing grub and fstab. I investigated the PCI assignments of the SCSI controllers, and it shows that the external one has PCI address 1:08.0 and 1:08.1, while the internal one has 5:06.0 and 5:06.1. There are three PCI slots I can use for the external card, and they come up as 0:xx.x, 1:xx.x and 2:xx.x, so there is no way to get the internal SCSI controller to appear earlier on the PCI bus than the external one. So the question is: can I stop the external array taking over sda? Any ideas, anyone? Paul. -- Paul Furness Systems Manager Visual Information Lab Mitsubsihi Electric ITE BV Guildford, UK Steepness is an illusion caused by flat things leaning over.