I want to migrate a IDE-using, LVM-based KVM guest running RHEL 6.5. I found this steps in this page:
1) Run virsh edit . From there, edit the config file and adjust all lines of
<target dev='hda' bus='ide'/>so they look like this
<target dev='vda' bus='virtio'/>Furthermore, remove all
<address type .../>lines so that libvirt can regenerate them appropriately.2) Inside the guest, edit /etc/fstab and replace all occurrences of /dev/sdX with /dev/vdX`.
3) That’s it, now shutdown the machine and start it with an virsh start (just a reboot inside the started VM won’t work).
Cool, seems easy but it doesn't cover the case with LVMs. Neither in my /etc/fstab nor in my /etc/grub.conf I found any /dev/sdX path that I could change (besides one commented in the grub.conf file). Should I do anything more with the lvms? The disk shown to the VM is a raw LUN comming from a multipathed equallogic SAN.
[root@testphys ~]# virsh domblklist aplitest
Target Source
------------------------------------------------
hda /dev/eql/vol-so-aplitest
hdc -
VM config file (extract with the disk configuration)
<disk type='block' device='disk'>
<driver name='qemu' type='raw' cache='none' io='native'/>
<source dev='/dev/eql/vol-so-aplitest'/>
<target dev='hda' bus='ide'/>
<address type='drive' controller='0' bus='0' target='0' unit='0'/>
</disk>
Guest's fdisk -l output for the disk (partition 2 is then used as the physical volume for the lvms shown in fstab below)
[root@aplitest ~]# fdisk -l
Disk /dev/sda: 118.1 GB, 118122086400 bytes
255 heads, 63 sectors/track, 14360 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0000fb75
Device Boot Start End Blocks Id System
/dev/sda1 * 1 64 512000 83 Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2 64 14361 114840576 8e Linux LVM
Guest's /etc/fstab
#
# /etc/fstab
# Created by anaconda on Fri Feb 28 15:51:07 2014
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/vg_aplitest-lv_root / ext4 defaults 1 1
UUID=0de4d0fc-3637-4b10-908f-7cde8d9347c2 /boot ext4 defaults 1 2
/dev/mapper/vg_aplitest-lv_home /home ext4 defaults 1 2
/dev/mapper/vg_aplitest-lv_opt /opt ext4 defaults 1 2
/dev/mapper/vg_aplitest-lv_tmp /tmp ext4 defaults 1 2
/dev/mapper/vg_aplitest-lv_usr /usr ext4 defaults 1 2
/dev/mapper/vg_aplitest-lv_var /var ext4 defaults 1 2
/dev/mapper/vg_aplitest-lv_var_log /var/log ext4 defaults 1 2
/dev/mapper/vg_aplitest-lv_swap swap swap defaults 0 0
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
Guest's /etc/grub.conf
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,0)
# kernel /vmlinuz-version ro root=/dev/mapper/vg_aplitest-lv_root
# initrd /initrd-[generic-]version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux Server (2.6.32-431.5.1.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-431.5.1.el6.x86_64 ro root=/dev/mapper/vg_aplitest-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_LVM_LV=vg_aplitest/lv_swap KEYBOARDTYPE=pc KEYTABLE=la-latin1 rd_LVM_LV=vg_aplitest/lv_root rd_NO_DM rhgb quiet
initrd /initramfs-2.6.32-431.5.1.el6.x86_64.img
title Red Hat Enterprise Linux (2.6.32-431.el6.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-431.el6.x86_64 ro root=/dev/mapper/vg_aplitest-lv_root rd_NO_LUKS LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_LVM_LV=vg_aplitest/lv_swap KEYBOARDTYPE=pc KEYTABLE=la-latin1 rd_LVM_LV=vg_aplitest/lv_root rd_NO_DM rhgb quiet
initrd /initramfs-2.6.32-431.el6.x86_64.img
Cheers,
