Re: Grub2 install with / on lvm

[Andrei Borzenkov]

В Wed, 4 Feb 2015 13:57:59 -0800 (PST)
address@hidden пишет:

> 
> Greetings -
>  
> I have been experimenting with an Linux Mint 17 installation for my desktop 
> system.  This is on a new Dell Precision 3610.  After having difficulties 
> getting the Mint installation to complete (grub2 install failed) with 
> software RAID (and trying the Intel IMSM fake raid) I finally purchased a 
> good hardware raid card and installed it in my system (LSI MegaRAID SAS 
> 9271-8i).  Now Mint installs without grub2 install failing during the 
> installation; however, at first boot I get sent to a grub prompt.  After 
> playing around with the SuperGrub2 Disk I think I have isolated the problem.  
> Here is a description of my system and what I have found.
>  
> 1.  RAID 1 of two 3-TB drives (entire drives, not partitions)
> 2.  Single drive recognized by BIOS and Mint installer as /dev/sda
> 3.  Created partitions and lvm logical volumes in GParted and command line 
> prior to install
>      /dev/sda1   500MB   /boot/efi   fat32
>      /dev/sda2   500MB   /boot   fat32

symbolic links are commonly used in /boot so fat32 is probably not the
best idea.

>      /dev/sda3   volume group vg_jab  (left 100MB unallocated at end)
>         lv_mintroot   8GB   /
>         lv_mintvar   4GB   /var
>         lv_mintswap   2GB   [swap]
>         lv_minthome   80GB   /home
>         lv_mintgis   1000GB   /gis
> 4.  I will be installing Windows 7 as a VM (using KVM) later in an additional 
> lv.
> 5.  Interestingly df-h does not show /dev/sda2, and ldblk does not show a 
> mount point for /dev/sda2
> 6.  Grub settings point to hd0, gpt1.  In grub I see a message of failure 
> reading sector ???? from hd1
>  

You said you have single disk, so there is no surprised grub cannot
read from hd1 - it should not exist. Where it comes from in grub
configuration?

> In SuperGrub2 Disk a linux boot image is not present when selecting 
> Everything.  If I select Everything+ a boot image appears.  Individually 
> going through the options in Extra Grub2 functionality, I get a linux boot 
> image to appear if all I do is enable grub2's LVM support.  I booted from 
> this installed image and tried running grub-install.  A reboot after that did 
> not resolve the issue.  It appears that my grub installation does not have 
> the support for lvm, and it appears that my root partition being on lvm is 
> likely the problem, as somewhere along this path I saw grub referencing the 
> UUID that is my lv_mintroot.

You do not say how you install bootloader. If you are using
distribution specific scripts you may have better luck on corresponding
list.

In general "grub-install /dev/sda" should figure out what drivers are
needed to access /boot/grub and include them in image. If /boot/grub is
on LVM, grub should include drivers for it in image. It is impossible
to say what is wrong without knowing exact procedure how grub was
installed.

>  
> I am looking for advice on what might be the best approach to take now.  I 
> have no problems if that means re-doing my partitions and taking / off of 
> lvm.  I am just not sure that is the only problem, or the entire solution, or 
> even the best solution overall.  I would like to hear what my options might 
> be before going through the reinstallation.
>  
> Please cc me directly, as I am only subscribed to the daily digest.  Thanks.
>  
> Jeff
>