Re: [gentoo-user] Can't boot btrfs

[Peter Humphrey]

On Friday 31 July 2015 06:44:54 Rich Freeman wrote:

> As Neil already pointed out, if you're not using an initramfs you need
> to put all your devices on this line if they're part of an array.  The
> kernel will not scan to find the others.

I didn't mention it the first time but I'd already tried 
device=/dev/sda3,device=/dev/sdb3 on the command line and it didn't help. I'd 
also tried the initramfs but that didn't help either. I'll try them again.

> If you do use an initramfs you really should use a UUID or label
> instead of a device name, but a device name will work as long as it
> happens to not get reordered on you.

I have only two SATA drives, both SSD, so even if they do get reordered they 
should still result in the same, no?

> > The other thing I've tried is to build an initramfs with dracut. I tried
> > to include its btrfs module but it refused because it couldn't find a
> > command btrfs. So I recompiled the kernel with btrfs as a module and added
> > 'filesystems+="btrfs" ' into dracut.conf. Still no success.
>
> Do you have btrfs-utils installed?

I have btrfs-progs, which I assume is what you mean.

> Dracut should work fine with btrfs built into the kernel natively or as a
> module, though if you want to boot directly it will have to be native

Yes, of course, I understand that. I tried it both ways round, as I said.

> I believe that as long as dracut can find the btrfs utility it will
> put it in the initramfs.

I'll check that again with lsinitrd.
 
> Otherwise there isn't much more to this - I think these two issues are
> the only real problems you're having, depending on which route you
> decide to take with the initramfs (which I still recommend, but you
> could of course have separate grub lines to boot with and without it
> if you want to experiment).

Indeed. Thank you both.

-- 
Rgds
Peter