Re: Grub2 install with / on lvm

[Andrei Borzenkov]

В Sat, 7 Feb 2015 09:03:38 -0800 (PST)
address@hidden пишет:

> Ok, I learned something new here.  What would be a better choice for the 
> filesystem for /boot.  I am using xfs for everything else.

I usually use ext2 if it is separate partition. Otherwise xfs should
work if /boot is not separate filesystem and is on root.

> 
> Grub was installed using the standard OS installation in Linux Mint 17.  I 
> haven't had much luck getting good knowledgable detailed answers there; more 
> speculation and hypotheses.  It is good to know that grub install would 
> normally include the LVM driver, so it is possible that Mint installation is 
> not recognizing that I am using LVM.  Is there a grub config file that would 
> identify the drivers that are pulled in, and I would be able to see if the 
> driver for LVM is included.  I don't want to get into hand editing grub 
> configuration files to get my system running.  I would prefer to have it 
> automatically the right way, I just want to understand what it did in case it 
> helps find or fix a bug in the Mint installation.

There are two pieces here. One is core.img that is loaded initially. It
includes grub modules (drivers) needed to access /boot/grub.
Unfortunately there is no easy way to see them. Another step is loading
operating system files. It is in /boot/grub/grub.cfg and you should
actually see "insmod lvm" there.

> 
> After I booted the system from the SuperGrub2 disk, I did run grub-install 
> /dev/sda just to see what would happen (since I was considering re-installing 
> anyway).  If I recall it ran without error, but still wouldn't boot and had 
> the same reference to hd1.

it may happen if you have incorrect /boot/grub/device.map. If you have
it, remove it. It is not needed by grub unless you have very unusual
configuration and have to work around some problem.

It may be useful to provide output of running
https://github.com/arvidjaar/bootinfoscript/raw/master/bootinfoscript
Upload it to pastebin or like.