Virtualization With KVM On An OpenSUSE 11.3 Server

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Author: Falko Timme <ft [at] falkotimme [dot] com>
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Last edited 01/03/2011

This guide explains how you can install and use KVM for creating and running virtual machines on an OpenSUSE 11.3 server. I will show how to create image-based virtual machines and also virtual machines that use a logical volume (LVM). KVM is short for Kernel-based Virtual Machine and makes use of hardware virtualization, i.e., you need a CPU that supports hardware virtualization, e.g. Intel VT or AMD-V.

I do not issue any guarantee that this will work for you!

1 Preliminary Note

I'm using an OpenSUSE 11.3 server with the hostname server1.example.com and the IP address 192.168.0.100 here as my KVM host.

We also need a desktop system where we install virt-manager so that we can connect to the graphical console of the virtual machines that we install. I'm using an OpenSUSE 11.3 desktop here.

2 Installing KVM

OpenSUSE 11.3 KVM Host:

First check if your CPU supports hardware virtualization - if this is the case, the command

egrep '(vmx|svm)' --color=always /proc/cpuinfo

should display something, e.g. like this:

server1:~ # egrep '(vmx|svm)' --color=always /proc/cpuinfo
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall
 nx mmxext fxsr_opt rdtscp lm 3dnowext 3dnow rep_good extd_apicid pni cx16 lahf_lm cmp_legacy svm extapic cr8_legacy 3dnowprefetch lbrv
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall
 nx mmxext fxsr_opt rdtscp lm 3dnowext 3dnow rep_good extd_apicid pni cx16 lahf_lm cmp_legacy svm extapic cr8_legacy 3dnowprefetch lbrv
server1:~ #

If nothing is displayed, then your processor doesn't support hardware virtualization, and you must stop here.

To install KVM and virtinst (a tool to create virtual machines), we run

yast2 -i kvm libvirt libvirt-python qemu virt-manager

Then create the system startup links for libvirtd...

chkconfig --add libvirtd

... and start the libvirt daemon:

/etc/init.d/libvirtd start

To check if KVM has successfully been installed, run

virsh -c qemu:///system list

It should display something like this:

server1:~ # virsh -c qemu:///system list
 Id Name                 State
----------------------------------

server1:~ #

If it displays an error instead, then something went wrong.

Next we need to set up a network bridge on our server so that our virtual machines can be accessed from other hosts as if they were physical systems in the network.

To do this, we install the package bridge-utils...

yast2 -i bridge-utils

... and configure a bridge.

To configure the bridge, create the file /etc/sysconfig/network/ifcfg-br0 as follows (make sure you use the IPADDR setting from the /etc/sysconfig/network/ifcfg-eth0 file):

vi /etc/sysconfig/network/ifcfg-br0

STARTMODE='auto'
BOOTPROTO='static'
IPADDR='192.168.0.100/24'
MTU=''
NETMASK=''
NETWORK=''
BROADCAST=''
USERCONTROL=no
NAME='Bridge 0'
NM_CONTROLLED=no
BRIDGE='yes'
BRIDGE_PORTS='eth0'
BRIDGE_AGEINGTIME='300'
BRIDGE_FORWARDDELAY='0'
BRIDGE_HELLOTIME='2'
BRIDGE_MAXAGE='20'
BRIDGE_PATHCOSTS='19'
BRIDGE_PORTPRIORITIES=
BRIDGE_PRIORITY=
BRIDGE_STP='on'

Modify /etc/sysconfig/network/ifcfg-eth0 as follows (set IPADDR to 0.0.0.0 and change STARTMODE to hotplug):

vi /etc/sysconfig/network/ifcfg-eth0

BOOTPROTO='static'
BROADCAST=''
ETHTOOL_OPTIONS=''
IPADDR='0.0.0.0'
MTU=''
NAME='MCP77 Ethernet'
NETMASK=''
NETWORK=''
REMOTE_IPADDR=''
STARTMODE='hotplug'
USERCONTROL='no'

Then restart the network:

/etc/init.d/network restart

Afterwards, run

ifconfig

It should now show the network bridge (br0):

server1:~ # ifconfig
br0       Link encap:Ethernet  HWaddr 00:1E:90:F3:F0:02
          inet addr:192.168.0.100  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::21e:90ff:fef3:f002/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:21 errors:0 dropped:0 overruns:0 frame:0
          TX packets:19 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:1446 (1.4 Kb)  TX bytes:3774 (3.6 Kb)

eth0      Link encap:Ethernet  HWaddr 00:1E:90:F3:F0:02
          inet6 addr: fe80::21e:90ff:fef3:f002/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:18882 errors:0 dropped:0 overruns:0 frame:0
          TX packets:13546 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:25589600 (24.4 Mb)  TX bytes:1324302 (1.2 Mb)
          Interrupt:28 Base address:0xe000

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:2 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:100 (100.0 b)  TX bytes:100 (100.0 b)

server1:~ #

3 Installing virt-manager On Your OpenSUSE 11.3 Desktop

OpenSUSE 11.3 Desktop:

We need a means of connecting to the graphical console of our guests - we can use virt-manager for this. I'm assuming that you're using an OpenSUSE 11.3 desktop.

Become root...

su

... and run...

yast2 -i virt-manager libvirt

... to install virt-manager.

(If you're using an Ubuntu 10.10 desktop, you can install virt-manager as follows:

sudo aptitude install virt-manager

)

4 Creating A Debian Lenny Guest (Image-Based)

OpenSUSE 11.3 KVM Host:

Now let's go back to our OpenSUSE 11.3 KVM host.

Take a look at

man virt-install

to learn how to use it.

I want to create my virtual machines in the directory /vm (they cannot be created in the /root directory because the qemu user doesn't have read permissions in that directory), so I have to create it first:

mkdir /vm

(If you try to create a virtual machine in the /root directory, you will get errors similar to this one:

server1:~ # virt-install --connect qemu:///system -n vm10 -r 512 --vcpus=2 -f ~/vm10.qcow2 -s 12 -c ~/debian-500-amd64-netinst.iso --vnc --noautoconsole --os-type linux --os-variant debianlenny --accelerate --network=bridge:br0 --hvm


Starting install...
Creating storage file vm10.qcow2                                 |  12 GB     00:00
ERROR    internal error Process exited while reading console log output: char device redirected to /dev/pts/2
qemu: could not open disk image /root/vm10.qcow2: Permission denied

Domain installation may not have been
 successful.  If it was, you can restart your domain
 by running 'virsh start vm10'; otherwise, please
 restart your installation.
ERROR    internal error Process exited while reading console log output: char device redirected to /dev/pts/2
qemu: could not open disk image /root/vm10.qcow2: Permission denied
Traceback (most recent call last):
  File "/usr/sbin/virt-install", line 972, in <module>
    main()
  File "/usr/sbin/virt-install", line 834, in main
    start_time, guest.start_install)
  File "/usr/sbin/virt-install", line 896, in do_install
    dom = install_func(conscb, progresscb, wait=(not wait))
  File "/usr/lib/python2.6/site-packages/virtinst/Guest.py", line 798, in start_install
    return self._do_install(consolecb, meter, removeOld, wait)
  File "/usr/lib/python2.6/site-packages/virtinst/Guest.py", line 899, in _do_install
    self.domain = self.conn.createLinux(install_xml, 0)
  File "/usr/lib64/python2.6/site-packages/libvirt.py", line 1147, in createLinux
    if ret is None:raise libvirtError('virDomainCreateLinux() failed', conn=self)
libvirtError: internal error Process exited while reading console log output: char device redirected to /dev/pts/2
qemu: could not open disk image /root/vm10.qcow2: Permission denied

server1:~ #

)

To create a Debian Lenny guest (in bridging mode) with the name vm10, 512MB of RAM, two virtual CPUs, and the disk image /vm/vm10.qcow2 (with a size of 12GB), insert the Debian Lenny Netinstall CD into the CD drive and run

virt-install --connect qemu:///system -n vm10 -r 512 --vcpus=2 -f /vm/vm10.qcow2 -s 12 -c /dev/cdrom --vnc --noautoconsole --os-type linux --os-variant debianlenny --accelerate --network=bridge:br0 --hvm

Of course, you can also create an ISO image of the Debian Lenny Netinstall CD...

dd if=/dev/cdrom of=/vm/debian-500-amd64-netinst.iso

... and use the ISO image in the virt-install command:

virt-install --connect qemu:///system -n vm10 -r 512 --vcpus=2 -f /vm/vm10.qcow2 -s 12 -c /vm/debian-500-amd64-netinst.iso --vnc --noautoconsole --os-type linux --os-variant debianlenny --accelerate --network=bridge:br0 --hvm

The output is as follows:

server1:~ # virt-install --connect qemu:///system -n vm10 -r 512 --vcpus=2 -f /vm/vm10.qcow2 -s 12 -c /vm/debian-500-amd64-netinst.iso --vnc --noautoconsole --os-type linux --os-variant debianlenny --accelerate --network=bridge:br0 --hvm


Starting install...
Creating storage file vm1 100% |=========================|  12 GB    00:00
Creating domain...                                                 0 B 00:00
Domain installation still in progress. You can reconnect to
the console to complete the installation process.
server1:~ #