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Re: Software RAID, LVM, and LILO on amd64 sarge

> To continue this thread a bit, I'm curious whether the current state  
> of boot loaders for Debian under amd64 is such that it is  
> theoretically possible to configure LVM on software RAID on a multi- 
> disk system without needing an isolated un-RAIDed /boot partition on  
> one of the disks.

It is certainly possible to have everything on RAID.
Currently, I have the root partition on RAID1, and the rest of the
system on LVM partitions, with the LVM physical disk being a RAID

[Although, when I installed, I had to first install the root
partition on a normal partition, boot the new system, compile a 
kernel with built-in RAID support, install "mdadm" and LVM, reboot 
in the new kernel, create the RAID devices, copy over the root (don't
forget the change the "fstab" file ;-), and reboot to get the new 

> I have a two-disk system. I'd like to create two RAID1s for this  
> system. One of the RAID1s would exist across a /boot partition with  
> the bootable flag set on each disk. 

Linux doesn't need this boot flag. [At least, it's not set on any of
my partitions, and the system boots nonetheless.]

> When I've tried this, I'm able to complete the  
> partition step, and then LILO is the only option, but it isn't able  
> to recognize /dev/md0 (or /dev/md/0) as a valid disk or partition.

I use GRUB.  IIRC the problem was that you need to use the 32 bits
version (which works fine); the 64 bits version has (had?) problems
with command-line completion...

You don't have to (I don't even know if it makes sense) install
the boot loader on the RAID device.  Just install it on (each of) the
real partitions that make up the RAID disk.
Also, unless you consider chain-loading, you should just install the
loader on the MBR, of your 2 physical disks: for GRUB, it's just a
matter of issuing "setup (hd0)" and "setup (hd1)" from inside the
grub shell.

> Is there any way to achieve what I want to do (preferably from the  
> installer), namely to have both disks have a bootable partition as  
> well as running LVM on RAID1 for the rest of the system?

I didn't try the recent installers.  When I installed (February), it
wasn't possible to do it all at once (hence the above procedure).


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