TODO: udelat tutorial :)

1. Instalace guestu:

   virt-install -n vps1 --ram=2048 --vcpus=2 --location='http://ftp.cz.debian.org/debian/dists/jessie/main/installer-amd64/' --disk path=/dev/shared_vg/vps1  --network bridge=br0 --os-type linux --console pty,target_type=serial --graphics none --os-variant generic --extra-args 'console=ttyS0,115200n8 serial'

2. v grubu pridat do radky linux

   console=tty0 console=ttyS0,115200

3. do /etc/default/grub pridat do GRUB_CMDLINE_LINUX_DEFAULT “console=tty0 console=ttyS0,115200”

   GRUB_CMDLINE_LINUX_DEFAULT="console=tty0 console=ttyS0,115200"

https://libvirt.org/remote.html

• note: nepovedlo se mi rozbehat

import libvirt
conn = libvirt.open("qemu+ssh://root@10.0.0.120")
 
# vypis bezicich vps (interni ID)
conn.listDomainsID()
 
# nalezeni vps podle ID (pouze bezici)
vps = conn.lookupByID(1)
 
# nalezeni vps podle jmena (bere i masiny, ktere jsou nebezici, ale nadefinovane)
vps1 = conn.lookupByName("vps1")
 
# spusteni
vps1.start()
 
# pause
vps1.suspend()
 
# unpause
vps1.resume()
 
# shut down
vps1.shutdown()
 
# force shutdown
vps1.destroy()
 
# close connection
conn.close()

• NOTE: we cannot use kvm migration, since we use mirrored clustered LVM (mirrored volume could not be activated on more than one node in time)
• use following script instead:

  #!/bin/bash
   
  if [ $# != 2 ]; then
          echo "Usage: move_vps.sh domain destination"
          exit 1
  fi
   
  MACHINE=$1
  DESTINATION=$2
   
  XML_NAME=/tmp/$MACHINE
  virsh dumpxml $MACHINE > $XML_NAME
  scp ${XML_NAME} root@${DESTINATION}:${XML_NAME}
  rm $XML_NAME
   
  IMG_NAME=/tmp/${MACHINE}.img
  virsh save $MACHINE $IMG_NAME
  scp $IMG_NAME root@${DESTINATION}:${IMG_NAME}
  rm $IMG_NAME
   
  lvchange -an /dev/shared_vg/$MACHINE
  ssh root@$DESTINATION "lvchange -ay /dev/shared_vg/$MACHINE"
  ssh root@$DESTINATION "virsh define ${XML_NAME}"
  ssh root@$DESTINATION "virsh restore $IMG_NAME"
  ssh root@$DESTINATION "rm $IMG_NAME"