Install GuestOS and create a Virtual Machine

Install GuestOS and create a Virtual Machine. This example shows to install CentOS 7.
[1]	Install GuestOS on text mode via network, it's OK on Console or remote connection with Putty and so on. Furthermore, Virtual Machine's images are placed at /var/lib/libvirt/images by default as a Storage Pool, but this example shows to create and use a new Storage Pool.

[root@dlp ~]#  mkdir -p /var/kvm/images  # create a new Storage Pool [root@dlp ~]#  virt-install \ --name centos7 \ --ram 4096 \ --disk path=/var/kvm/images/centos7.img,size=30 \ --vcpus 2 \ --os-type linux \ --os-variant rhel7 \ --network bridge=br0 \ --graphics none \ --console pty,target_type=serial \ --location 'http://ftp.iij.ad.jp/pub/linux/centos/7/os/x86_64/' \ --extra-args 'console=ttyS0,115200n8 serial' Starting install... # start installation

The example of options above means like follows. There are many options for others, make sure with "man virt-install". --name specify the name of Virtual Machine --ram specify the amount of memories of Virtual Machine --disk path=xxx ,size=xxx 'path=' ⇒ specify the location of disks of Virtual Machine 'size=' ⇒ specify the amount of disks of Virtual Machine --vcpus specify the virtual CPUs --os-type specify the type of GuestOS --os-variant specify the kind of GuestOS - possible to confirm the list with the command below # osinfo-query os --network specify network types of Virtual Machine --graphics specify the kind of graphics. if set 'none', it means nographics. --console specify the console type --location specify the location of installation where from --extra-args specify parameters that is set in kernel

[2]	Install on text mode, it's the same with common procedure of installation. After finishing installation, reboot first and then login prompt is shown like follwos.

CentOS Linux 7 (Core) Kernel 3.10.0-123.el7.x86_64 on an x86_64 localhost login:

[3]	Move to GuestOS to HostOS with Ctrl + ] key. Move to HostOS to GuestOS with a command 'virsh console (name of virtual machine)'.

[root@localhost ~]#  # push Ctrl + ] [root@dlp ~]#  # Host's console [root@dlp ~]#  virsh console centos7  # move to Guest Connected to domain www Escape character is ^]  # Enter key [root@localhost ~]#  # Guest's console

[4]	Because after installing GuestOS from network, it is minimum settings, so it's useful to save it as a template in order to create new virtual machines later.

[root@dlp ~]#  virt-clone --original centos7 --name template --file /var/kvm/images/template.img  Allocating 'template.img'  | 20 GB 01:44 Clone 'template' created successfully. [root@dlp ~]#  ll /var/kvm/images/template.img     # disk image -rwxr-xr-x 1 root root 32212254720 Jul 11 23:34 /var/kvm/images/template.img [root@dlp ~]#  ll /etc/libvirt/qemu/template.xml     # xml file -rw------- 1 root root 1843 Jul 11 23:32 /etc/libvirt/qemu/template.xml

[5]	Set basic initial configuration to GuestOS first before using it.
[6]	Define a new Storage Pool.

[root@dlp ~]#  mkdir /etc/libvirt/storage  [root@dlp ~]#  vi /etc/libvirt/storage/disk01.xml    # create new <pool type='dir'>    # any name you like   <name>disk01</name>   <capacity>0</capacity>   <allocation>0</allocation>   <available>0</available>   <source>   </source>   <target>      # specify a pool directory     <path>/var/kvm/images</path>     <permissions>         <mode>0700</mode>         <owner>-1</owner>         <group>-1</group>     </permissions>   </target> </pool> # define the pool [root@dlp ~]#  virsh pool-define /etc/libvirt/storage/disk01.xml  Pool disk01 defined from /etc/libvirt/storage/disk01.xml # start the pool [root@dlp ~]#  virsh pool-start disk01  Pool disk01 started # set auto-start [root@dlp ~]#  virsh pool-autostart disk01  Pool disk01 marked as autostarted # confirm to show the pool list [root@dlp ~]#  virsh pool-list  Name State Autostart ----------------------------------------- disk01 active yes # confirm to show the details [root@dlp ~]#  virsh pool-info disk01  Name: disk01 UUID: 2de62477-7132-4512-b5d8-003e28da105c State: running Persistent: yes Autostart: yes Capacity: 197.17 GiB Allocation: 2.90 GiB Available: 194.27 GiB