This is a collection of notes I took while setting up a virtual machine host which has several guest virtual machines running on Ubuntu 8.10.
1) Create a logical volume to install the guest
$ sudo lvcreate -v -n phq_mail -L 80G vg0 /dev/md1
Setting logging type to disk
Finding volume group \"vg0\"
Creating directory \"/etc/lvm/archive\"
Archiving volume group \"vg0\" metadata (seqno 6).
Creating logical volume phq_mail
Creating volume group backup \"/etc/lvm/backup/vg0\" (seqno 7).
Found volume group \"vg0\"
Creating vg0-phq_mail
Loading vg0-phq_mail table
Resuming vg0-phq_mail (254:5)
Clearing start of logical volume \"phq_mail\"
Creating volume group backup \"/etc/lvm/backup/vg0\" (seqno 7).
Logical volume \"phq_mail\" created
Remember you can view all your logical volumes using lvdisplay
2) Creating a network segment to separate the servers from the rest of the network (the clients will use routing through the host to access the server).
$ vim ~/pofhq-servers.xml
<network>
<name>default</name>
<uuid>e81218cf-6d5a-4a6f-8af8-b2d5b77947be</uuid>
<bridge name=\"virbr%d\" />
<forward/>
<ip address=\"192.168.25.1\" netmask=\"255.255.255.0\">
<dhcp>
<range start=\"192.168.25.2\" end=\"192.168.25.30\" />
</dhcp>
</ip>
</network>
$ virsh net-define pofhq-servers.xml
Network pofhq-servers defined from pofhq-servers.xml
$ virsh net-create pofhq-servers.xml
Network pofhq-servers created from pofhq-servers.xml
$ virsh net-autostart pofhq-servers
Network pofhq-servers marked as autostarted
$ rm ~/pofhq-servers.xml
This will create the file pofhq-servers.xml into /etc/libvirt/qemu/networks and link it to autostart folder.
Optionally, if you don’t want to use the ‘default’ network segment, you can delete it:
$ virsh net-undefine default $ virsh net-destroy default
This will automatically delete de default-network.xml file (and autostart symlink if present) on /etc/libvirt/qemu/networks.
3) Installing the guest operating system using virtio for best virtual machine network and disk performance
We will start by letting virt-install create the default VM template for us:
$ sudo virt-install -n phq_mail -r 1024 -f /dev/vg0/phq_mail -c ubuntu-server.iso --accelerate --vnc --noautoconsole -v Starting install... Creating domain... 0 B 00:00 Domain installation still in progress. You can reconnect to the console to complete the installation process.
Right after this, we will stop the VM and edit it’s configuration manually:
$ virsh shutdown phq_mail $ virsh dumpxml phq_mail > phq_mail.xml $ virsh undefine phq_mail $ virsh destroy phq_mail $ vim phq_mail.xml
Make the following modifications:
- Boot from CD:
<os>
<type>hvm</type>
<boot dev='cdrom'/>
</os>
<disk type='file' device='cdrom'>
<source file='/home/pau/ubuntu-8.10-server-i386.iso'/>
<target dev='hdc' bus='ide'/>
<readonly/>
</disk>
- Use virtio for the hard disk:
<disk type='block' device='disk'>
<source dev='/dev/vg0/phq_mail'/>
<target dev='vda' bus='virtio'/>
</disk>
- Use virtio for the network:
<interface type='network'>
<mac address='00:16:36:7a:7b:7c'/>
<source network='pofhq-servers'/>
<model type='virtio'/>
</interface>
Save the file, and create again the virtual machine with the new config:
$ virsh define phq_mail.xml Connecting to uri: qemu:///system Domain phq_mail defined from phq_mail.xml $ virsh create phq_mail.xml Connecting to uri: qemu:///system Domain phq_mail created from phq_mail.xml $ virsh autostart phq_mail Connecting to uri: qemu:///system Domain phq_mail marked as autostarted
Install normally, and then change the boot option to ‘hd’ to boot from normal hard disk again when installation has been finished (if needed, use shutdown/undefine/destroy and define/create/autostart again after finishing the installation).
4) If the guest VM you have installed is Ubuntu, remember to install acpid, for the VM to shutdown cleanly.
5) Useful documentation:
Google+
linkedin.com/in/pauoliva
twitter.com/pof