From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bill Davidsen Subject: Re: Does grub support sw raid1? Date: Wed, 22 Mar 2006 08:28:28 -0500 Message-ID: <442150FC.2060903@tmr.com> References: <442020AD.7090902@cc.kuleuven.be> <44202F7A.80901@h3c.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <44202F7A.80901@h3c.com> Sender: linux-raid-owner@vger.kernel.org To: Mike Hardy Cc: Herta Van den Eynde , linux-raid@vger.kernel.org, redhat-list@redhat.com List-Id: linux-raid.ids Mike Hardy wrote: >This works for me, there are several pages out there (I recall using the >commands from a gentoo one most recently) that show the exact sequence >of grub things you should do to get grub in the MBR of both disks. > >It sounds like your machine may not be set to boot off of anything other >than that one disk though? Is that maybe a BIOS thing? > >I dunno, but I have definitely pulled a primary drive out of the system >completely and booted off the second one, then had linux come up with >(correctly) degraded arrays > > Frequently a BIOS will boot a 2nd drive if the first is missing/dead, but not if it returns bad data (CRC error). A soft fail is not handled correctly by all BIOS' in use, possibly a majority of them. >-Mike > >Herta Van den Eynde wrote: > > >>(crossposted to linux-raid@vger.kernel.org and redhat-list@redhat.com) >>(apologies for this, but this should have be operational last week) >> >>I installed Red Hat EL AS 4 on a HP Proliant DL380, and configured all >>system devices in software RAID 1. I added an entry to grub.conf to >>fallback to the second disk in case the first entry fails. At boottime, >>booting from hd0 works fine. As does booting from hd1. >> >>Until I physically remove hd0 from the system. >> >>I tried manually installing grub on hd1, >>I added hd1 to the device.map and subsequently re-installed grub on it, >>I remapped hd0 to /dev/cciss/c0d1 and subsequently re-installed grub >>all to no avail. >> >>I previously installed this while the devices were in slots 2 and 3. The >>system wouldn't even boot then. It looks as though booting from sw >>RAID1 will only work when there's a valid device in slot 0. Still >>preferable over hw RAID1, but even better would be if this worked all >>the way. >> >>Is this working for anyone? Any idea what I may have overlooked? Any >>suggestions on how to debug this? >> >>Kind regards, >> >>Herta >> >>Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm >> -- bill davidsen CTO TMR Associates, Inc Doing interesting things with small computers since 1979