Creating lvm-based vm from installed RHEL distro

Goal

Our mission is to create on running vm separate /boot/ partition on /dev/vda1 and lvm partitions on /dev/vda2 (with lvroot, lvtmp, lvopt, lvvar, lvusr, lvswap)

Rhel6.7

1. Create volume, attach it to vm
   qemu-img create -f qcow2 25G rhel6_2.qcow2 virsh attach-disk rhel6 rhel6_2.qcow2 vdb
2. Start vm and logon
   virsh start rhel6 && virt-viewer rhel6
3. Make partition on /dev/vdb and create fs on /dev/vdb1 ( it will be our /boot partition )
   (echo n; echo p; echo 1; echo ; echo +200MB; echo a; echo 1; echo n;echo p; echo 2; echo ; echo ; echo t; echo 2; echo 8e; echo w) | fdisk /dev/vdb mkfs.ext4 -I 128 /dev/vdb1
4. Mount /dev/vdb1 to /mnt/ and copy all files from /boot/ to /mnt/, execute grub-install
   echo "(hd1) /dev/vdb" >> /boot/grub/device.map mount /dev/vdb1 /mnt/ rm -rf /mnt/* find /boot/ -xdev | cpio -pvmd /mnt grub-install --root-directory=/mnt/ /dev/vdb
5. Change kernel lines in grub config, install lvm2 and regenerate initramfs for lvm support. Copy MBR from old /dev/vda to new /dev/vdb
   sed -i 's|.*kernel /boot/vmlinuz-2.6.32-573.el6.x86_64 ro.| kernel /boot/vmlinuz-2.6.32-573.el6.x86_64 ro root=/dev/mapper/rootvg-lvroot rd_NO_LUKS KEYBOARDTYPE=pc KEYTABLE=us LANG=en_US.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto console=tty0 console=ttyS0,115200n8 no_timer_check rd_NO_DM rhgb quiet|' /mnt/boot/grub/grub.conf yum install -y lvm2 rm -rf /var/cache/ cd /mnt/boot/ mv initramfs-uname -r.img initramfs-uname -r.img.bak dracut -f initramfs-uname -r.img uname -r cd; umount /mnt/ dd if=/dev/vda of=/dev/vdb bs=446 count=1
6. Create lvm vggroup and lvpartitons
   vgcreate rootvg -s 32MB /dev/vdb2 lvcreate -L 2G -n lvroot rootvg lvcreate -L 4G -n lvhome rootvg lvcreate -L 4G -n lvtmp rootvg lvcreate -L 4G -n lvusr rootvg lvcreate -L 4G -n lvvar rootvg lvcreate -L 2G -n lvopt rootvg lvcreate -L 2G -n lvswap rootvg mkfs.ext4 /dev/mapper/rootvg-lvroot mkfs.ext4 /dev/mapper/rootvg-lvtmp mkfs.ext4 /dev/mapper/rootvg-lvusr mkfs.ext4 /dev/mapper/rootvg-lvhome mkfs.ext4 /dev/mapper/rootvg-lvopt mkfs.ext4 /dev/mapper/rootvg-lvvar mkswap /dev/mapper/rootvg-lvswap
7. Mount /dev/mapper/rootvg-lvroot to /mnt/, copy all from / and delete all unnecessary files from dirs /mnt/opt/ /mnt/boot/ /mnt/tmp/ /mnt/var/ /mnt/usr/ /mnt/home/. Change lines in fstab
   mount /dev/mapper/rootvg-lvroot /mnt/ rm -rf /mnt/* rsync -avxHAX --progress --whole-file / /mnt/ rm -rf /mnt/boot/* rm -rf /mnt/var/* rm -rf /mnt/usr/* rm -rf /mnt/home/* rm -rf /mnt/tmp/* rm -rf /mnt/opt/* sed -i 's|.UUID.|/dev/mapper/rootvg-lvroot / ext4 errors=remount-ro 0 1|' /mnt/etc/fstab echo "/dev/vda1 /boot ext4 defaults 0 2" >> /mnt/etc/fstab echo "/dev/mapper/rootvg-lvhome /home ext4 defaults 0 2" >> /mnt/etc/fstab echo "/dev/mapper/rootvg-lvopt /opt ext4 defaults 0 2" >> /mnt/etc/fstab echo "/dev/mapper/rootvg-lvtmp /tmp ext4 defaults 0 2" >> /mnt/etc/fstab echo "/dev/mapper/rootvg-lvusr /usr ext4 defaults 0 2" >> /mnt/etc/fstab echo "/dev/mapper/rootvg-lvvar /var ext4 defaults 0 2" >> /mnt/etc/fstab echo "/dev/mapper/rootvg-lvswap none swap sw 0 0" >> /mnt/etc/fstab umount /mnt/
8. Mount and repeate step 7 on others partitions
   mount /dev/mapper/rootvg-lvtmp /mnt/ rm -rf /mnt/* rsync -avxHAX --progress --whole-file /tmp/ /mnt/ umount /mnt/ mount /dev/mapper/rootvg-lvusr /mnt/ rm -rf /mnt/* rsync -avxHAX --progress --whole-file /usr/ /mnt/ umount /mnt/ mount /dev/mapper/rootvg-lvvar /mnt/ rm -rf /mnt/* rsync -avxHAX --progress --whole-file /var/ /mnt/ umount /mnt/ mount /dev/mapper/rootvg-lvhome /mnt/ rm -rf /mnt/* rsync -avxHAX --progress --whole-file /home/ /mnt/ umount /mnt/ mount /dev/mapper/rootvg-lvopt /mnt/ rm -rf /mnt/* rsync -avxHAX --progress --whole-file /opt/ /mnt/ umount /mnt/ shutdown -h now
9. Profit

##RHEL7

1. Almost identically, but
   grub2-install --root-directory=/mnt/ /dev/vdb vdb1id=lsblk -f | grep vdb1 | awk '{print $3}' sed -i "s/.search --no-floppy --fs-uuid --set=root --hint='hd0,msdos1'./ search --no-floppy --fs-uuid --set=root --hint='hd0,msdos1' $vdb1id/" /mnt/boot/grub2/grub.cfg sed -i "s|.linux16 /boot/vmlinuz-3.10.0-327.10.1.el7.x86_64 root=UUID.| linux16 /boot/vmlinuz-3.10.0-327.10.1.el7.x86_64 root=/dev/mapper/rootvg-lvroot ro console=tty0 console=ttyS0,115200n8 no_timer_check net.ifnames=0 crashkernel=auto rd.lvm.lv=rootvg/lvroot rd.lvm.lv=rootvg/lvswap rd.lvm.lv=rootvg/lvtmp rd.lvm.lv=rootvg/lvusr rd.lvm.lv=rootvg/lvvar rd.lvm.lv=rootvg/lvopt rd.lvm.lv=rootvg/lvhome LANG=en_US.UTF-8|" /mnt/boot/grub2/grub.cfg