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on Thursday 04/24/2008 Alan McKinnon(alan.mckinnon@×××××.com) wrote |
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> On Thursday 24 April 2008, reader@×××××××.com wrote: |
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> |
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> > So assuming I've made some mistake in grub.conf I try to boot from |
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> > grub command line. |
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> > |
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> > root = (hd0,0) (which is /dev/sda1 in linux terms) |
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> > |
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> > kernel /kernel-2.6.25-r1 |
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> |
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> Nope. Kernel needs a root=<device> parameter. It can't know what is your |
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> root partition, that info is in fstab and fstab is on the root |
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> partition.So you tell it via a parameter |
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> |
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> > boot |
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> > |
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> > But it fails with a message saying please append a working root=?? to |
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> > the boot commands. |
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> |
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> expected result. see above. |
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> |
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> |
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> > So reloading the install ISO I mount /mnt/gentoo/boot and edit |
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> > grub.conf to say: |
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> > |
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> > title=kernel-2.6.25-r1 |
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> > root (hd0,0) |
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> > kernel /kernel-2.6.25-r1 root=/dev/sda3 |
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> > |
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> > That fails |
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> > kernel /kernel-2.6.25-r1 root=/dev/hda3 (Thinking maybe grub |
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> > does not understand sda) |
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> |
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> Nothing to do with grub. It's a kernel boot parameter passed verbatim to |
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> the kernel and needs valid kernel device names. |
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> |
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> What's the error you get? Is (hd0,0) a separate /boot? Does it contain a |
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> file called kernel-2.6.25-r1 at the top level? And you also should have |
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> a "ro" kernel parameter in there |
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> |
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> > That Fails |
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> > |
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> > kernel /kernel-2.6.25-r1 root=(hd0)/sda3 |
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> > |
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> > Fails |
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> |
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> Won't work. (hd0) is a grub thing. You need a /dev/sda3 or similar in |
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> there |
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> |
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> > I've even tried: |
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> > kernel /kernel-2.6.25-r1 root=(hd0,2) |
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> |
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> Won't work. Same reason. |
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> |
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> > And another failure... all with the same message about appending a |
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> > working `root=???' |
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> > |
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> > I'm about out of ideas here. |
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> |
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> here's a working grub.conf for illustration: |
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> |
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> default 0 |
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> timeout 10 |
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> splashimage=(hd0,0)/grub/splash.xpm.gz |
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> |
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> title Default |
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> root (hd0,0) |
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> kernel /vmlinuz root=/dev/sda3 ro |
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> |
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> title Gentoo-2.6.25 |
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> root (hd0,0) |
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> kernel /vmlinuz-2.6.25-gentoo root=/dev/sda3 ro |
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> |
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> Seems my setup is identical to yours: |
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> /boot on /dev/sda1 aka (hd0,0) to grub |
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> / on /dev/sda3 |
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> |
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> Only difference is the "ro" boot parameter, which shouldn't make a |
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> difference - it's there for fsck purposes during start-up. |
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> |
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> What disk driver and disks do you have? Are you 100% sure you are either |
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> using the new ata driver (everything is an sd) or have scsi/sata disks? |
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> If your disk is IDE with the old driver, it will be an hd and will |
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> require that on the kernel line |
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> |
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|
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Well, I had to put a lot more parameters for it to work -- I am not |
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using grub but my parameters aside from the ro are |
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init=/linuxrc ramdisk=8192 real_root=/dev/sda2 udev |
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and some more specific to me. I am using something close to the |
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original gentoo configs, so it uses an initrd parameter also which you |
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need separately in grub. |
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|
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Hope this helps. |
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|
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-- |
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Your life is like a penny. You're going to lose it. The question is: |
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How do |
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you spend it? |
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|
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John Covici |
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covici@××××××××××.com |
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-- |
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