Xen kernel panic - LVM volumes not accessible

[lmacka]

I have followed the howto here:
http://www.howtoforge.com/virtualiza...virtualization

I'm trying to install on a Dell R720 with a hardware RAID5 configuration and 4 cores. The RAID's configured so I have a single ~3TB volume, /dev/sda

I've followed the tutorial all the way to the point where I reboot into my new kernel. When booting, xen.gz appears and loads properly, then the kernel also appears to load but ends up in a kernel panic with the following output:


...
dracut Warning: No root device "block:/dev/mapper/vg_cbcxen-lv_root" found
dracut Warning: LVM vg_cbcxen/lv_swap not found
dracut Warning: LVM vg_cbcxen/lv_root not found

Obviously it's having problems finding my LVMs or a required driver isn't loading. I've searched the web but to no avail. Hoping someone here can point me in the right direction...

My grub.conf is as follows:

default=0
timeout=30
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title CentOS (2.6.32.57-2.el6xen.x86_64)
        root (hd0,0)
        kernel /xen.gz dom0_mem=1024M cpufreq=xen dom0_max_vcpus=4 dom0_vcpus_pin
        module /vmlinuz-2.6.32.57-2.el6xen.x86_64 ro root=/dev/mapper/vg_cbcxen-lv_root nomodeset rd_NO_LUKS rd_LVM_LV=vg_cbcxen/lv_swap LANG=en_US.UTF-8 rd_LVM_LV=vg_cbcxen/lv_root rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM
        module /initramfs-2.6.32.57-2.el6xen.x86_64.img
title CentOS (2.6.32-279.el6.x86_64)
        root (hd0,0)
        kernel /vmlinuz-2.6.32-279.el6.x86_64 ro root=/dev/mapper/vg_cbcxen-lv_root nomodeset rd_NO_LUKS rd_LVM_LV=vg_cbcxen/lv_swap LANG=en_US.UTF-8 rd_LVM_LV=vg_cbcxen/lv_root rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto  KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet
        initrd /initramfs-2.6.32-279.el6.x86_64.img

Version and file info:

[root@cbcxen ~]# rpm -qa | grep xen
xen-libs-4.1.3-1.el6.x86_64
xen-runtime-4.1.3-1.el6.x86_64
xen-4.1.3-1.el6.x86_64
kernel-xen-2.6.32.57-2.x86_64
kernel-xen-release-6-3.noarch
xen-licenses-4.1.3-1.el6.x86_64
xen-hypervisor-4.1.3-1.el6.x86_64
xen-devel-4.1.3-1.el6.x86_64
[root@cbcxen ~]# ls -l /boot/
total 52801
-rw-r--r--. 1 root root   101820 Jun 22 19:44 config-2.6.32-279.el6.x86_64
-rw-r--r--  1 root root    95612 May 25 11:25 config-2.6.32.57-2.el6xen.x86_64
drwxr-xr-x. 3 root root     1024 Aug 18 23:41 efi
drwxr-xr-x. 2 root root     1024 Aug 20 22:13 grub
-rw-r--r--. 1 root root 14822507 Aug 18 23:41 initramfs-2.6.32-279.el6.x86_64.img
-rw-r--r--  1 root root 12620635 Aug 20 21:43 initramfs-2.6.32.57-2.el6xen.x86_64.img
drwx------. 2 root root    12288 Aug 18 23:08 lost+found
-rw-r--r--. 1 root root   179157 Jun 22 19:45 symvers-2.6.32-279.el6.x86_64.gz
-rw-r--r--  1 root root   157712 May 25 11:25 symvers-2.6.32.57-2.el6xen.x86_64.gz
-rw-r--r--. 1 root root  2341856 Jun 22 19:44 System.map-2.6.32-279.el6.x86_64
-rw-r--r--  1 root root  2178713 May 25 11:25 System.map-2.6.32.57-2.el6xen.x86_64
-rwxr-xr-x. 1 root root  3986608 Jun 22 19:44 vmlinuz-2.6.32-279.el6.x86_64
-rw-r--r--  1 root root  3495856 May 25 11:25 vmlinuz-2.6.32.57-2.el6xen.x86_64
-rw-r--r--. 1 root root   737584 Aug 11 12:08 xen-4.1.3.gz
lrwxrwxrwx. 1 root root       12 Aug 18 23:56 xen-4.1.gz -> xen-4.1.3.gz
lrwxrwxrwx. 1 root root       12 Aug 18 23:56 xen.gz -> xen-4.1.3.gz
-rw-r--r--. 1 root root 13317834 Aug 11 12:08 xen-syms-4.1.3
[root@cbcxen ~]# parted
GNU Parted 2.1
Using /dev/sda
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) print all
Model: DELL PERC H710 (scsi)
Disk /dev/sda: 2999GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt

Number  Start   End     Size    File system  Name  Flags
 1      1049kB  525MB   524MB   ext4               boot
 2      525MB   2999GB  2998GB                     lvm


Error: partition length of 5735235584 sectors exceeds the loop-partition-table-imposed maximum of 4294967295

Model: Linux device-mapper (linear) (dm)
Disk /dev/mapper/vg_cbcxen-lv_swap: 8305MB
Sector size (logical/physical): 512B/512B
Partition Table: loop

Number  Start  End     Size    File system     Flags
 1      0.00B  8305MB  8305MB  linux-swap(v1)


Model: Linux device-mapper (linear) (dm)
Disk /dev/mapper/vg_cbcxen-lv_root: 53.7GB
Sector size (logical/physical): 512B/512B
Partition Table: loop

Number  Start  End     Size    File system  Flags
 1      0.00B  53.7GB  53.7GB  ext4

Note that I'm planning on shrinking that /home volume and setting up LVM based VMs.

TIA for any assistance...

[lmacka]

Further progressing down the track of trial and error, I thought the problem might be related to a lack of LVM support in the initramfs that the new kernel was loading, so I made my own with pretty much everything in it that could be used. Here's the command I used to do it after booting into my good kernel.

dracut --force -a 'base lvm kernel-modules dm rootfs-block' --add-drivers 'scsi_mod scsi_wait_scan ext4 megaraid_sas sd_mod ahci wmi dm_mirror dm_region_hash dm_log dm_mod tg3' --nomdadmconf --lvmconf -v /boot/initramfs-2.6.32.57-2.el6xen.x86_64.img 2.6.32.57-2.el6xen.x86_64

It didn't work, but since there's a lack of examples around for this command I thought I'd post it anyway. I realize that there's some addition fluff in there that I don't need. Trial and error.

So my initramfs definitely has LVM and Dell PERC driver support in it, must be a configuration issue.
I'm almost out of ideas.... Help?

[lmacka]

Tried updating the megaraid_sas module as per this article:
http://www.mentby.com/pasi-kaerkkaei...-adapters.html

Didn't help in my case.