Libvirt Host

This role sets up a host to work as a Libvirt/KVM hypervisor. It can also set up storage pools and networks on that host.

Requirements

The host must have Virtualization Technology (VT) turned on.

Role Variables

libvirt_host_pools is a list of storage pools to create and activate. Each entry should include:

• name: The pool's name.
• type: The pool type, with current options being dir, logical, or rbd. Note: lvm2 can be used as an old name for logical, but it will be removed in the future.
• capacity: The storage size in bytes for the pool (optional).
• path: The full path to where the pool's directory is located.
• mode: The access mode for the pool (only applicable for dir). Provide as an integer without a leading zero (example: mode: 755).
• owner: The pool's owner (only applicable for dir).
• group: The pool's group (only applicable for dir).
• source: The volume group name if the type is logical, or the RBD pool name if the type is rbd.
• pvs: A list of physical volumes that make up this volume group (only for logical).
• hosts: List of IPs or hostnames for Ceph monitors (only for rbd).
• username: The username for RADOS authentication (only for rbd).
• passphrase: The passphrase for RADOS authentication (only for rbd).

libvirt_host_networks is a list of networks to set up. Each entry should include:

• name: The network's name.
• mode: The network's forwarding mode, options are bridge, route, open, and nat. Leave it empty for an isolated network.
• bridge: The name of the bridge interface.
• ip: The IP address for the virtual bridge, needed for route, open, and nat modes.
• netmask: The netmask for the virtual bridge, required for route, open, and nat modes.
• domain: The DNS domain name for route, open, and nat modes, defaults to the network name (optional).
• dhcp_start: The first IP in the DHCP range for route, open, or nat modes (optional).
• dhcp_end: The last IP in the DHCP range for route, open, or nat modes (optional).
• routes: Optional extra routes can be defined, including:
  • address: The route's address (required).
  • prefix: The route's prefix (required).
  • gateway: The route's gateway (required).
  • metric: The route's metric (optional).
• ipv6: The IPv6 address for the virtual bridge (optional).
• ipv6_prefix: The IPv6 prefix for the virtual bridge (optional).
• routesv6: Optional extra IPv6 routes defined as before.

libvirt_host_require_vt: Indicates if Intel Virtualization Technology (VT) must be enabled to run this role. Although it enhances VM performance, it may not be available in some setups. Default is true.

libvirt_host_qemu_emulators: Specifies the architectures for which to install QEMU system emulators, e.g., x86. If libvirt_host_require_vt is false, the default value is ['x86'], otherwise, it is an empty list.

libvirt_host_enable_efi_support: Indicates whether to enable EFI support, defaults to false due to the need for additional packages.

libvirt_host_var_prefix: Sets the directory in /var/run that libvirt uses for state storage, e.g., Unix domain sockets, and the default PID file name. Override if there is a naming conflict, defaults to "".

libvirt_host_socket_dir: Location where the libvirtd socket is created. Defaults to /var/run/{{ libvirt_host_var_prefix }} if libvirt_host_var_prefix is set, otherwise "".

libvirt_host_pid_path: Path to the PID file to prevent multiple daemon instances. Defaults to /var/run/{{ libvirt_host_var_prefix }}.pid if libvirt_host_var_prefix is set, otherwise "".

libvirt_host_libvirtd_args: Command-line options passed to libvirtd when it starts—quotes will be added automatically.

libvirt_host_uri: The connection URI for libvirt. Defaults to qemu+unix:///system?socket={{ libvirt_host_socket_dir }}/libvirt-sock if libvirt_host_var_prefix is set, otherwise "". If set to a false value, no specific connection URI will be used in virsh or any virt_ Ansible modules.

libvirt_host_python3: Specifies if the Python 3 version of the libvirt bindings should be installed. If false, the Python 2 bindings will be installed.

libvirt_host_install_daemon: Indicates if the libvirt daemon should be installed and activated. Default is true.

libvirt_host_install_client: Indicates if the libvirt client should be installed and activated. Default is true.

libvirt_host_extra_daemon_packages: List of extra packages to install on libvirt daemon hosts.

libvirt_host_extra_client_packages: List of extra packages to install on libvirt client hosts.

libvirt_host_libvirtd_conf_enabled: Indicates if libvirtd.conf should be set up. Default is true.

libvirt_host_libvirtd_conf: Configuration settings for libvirtd.conf. A dictionary mapping option names to values. Default is empty.

libvirt_host_qemu_conf_enabled: Indicates if qemu.conf should be set up. Default is true.

libvirt_host_qemu_conf: Configuration settings for qemu.conf. A dictionary mapping option names to values. Default is empty.

libvirt_host_enable_sasl_support: Determines if SASL authentication support should be enabled. Default is false.

libvirt_host_sasl_conf_enabled: Indicates if SASL authentication should be configured (/etc/sasl2/libvirt.conf). Default matches libvirt_host_enable_sasl_support.

libvirt_host_sasl_conf: Configuration settings for SASL (/etc/sasl2/libvirt.conf). A string.

libvirt_host_sasl_mech_list: List of enabled libvirt SASL authentication methods. Default is ["SCRAM-SHA-256"] when libvirt_host_tls_listen is true, otherwise ["DIGEST-MD5"].

libvirt_host_sasl_credentials: List of SASL authentication credentials to create, with each item being a dict containing username and password. Default is a list with a single item containing libvirt_host_sasl_authname and libvirt_host_sasl_password.

libvirt_host_sasl_authname: The username for SASL authentication. Default is libvirt.

libvirt_host_sasl_password: The password for SASL authentication. Default is unset.

libvirt_host_sasl_auth_conf_enabled: Indicates if SASL authentication credentials should be configured (/etc/libvirt/auth.conf). Default matches libvirt_host_enable_sasl_support.

libvirt_host_sasl_auth_conf: Configuration settings for SASL authentication credentials (/etc/libvirt/auth.conf). A string.

libvirt_host_sasl_auth_conf_filename: Name of the file to save SASL authentication credentials. Default is "/etc/libvirt/auth.conf".

libvirt_host_sasl_auth_conf_owner: Owner of the file for SASL credentials. Default is "root".

libvirt_host_sasl_auth_conf_group: Group for the file for SASL credentials. Default is "root".

libvirt_host_sasl_auth_conf_mode: Permissions for the file for SASL credentials. Default is "0600".

libvirt_host_tcp_listen: Indicates if the TCP socket unit should be enabled via systemd. Default is false.

libvirt_host_tcp_listen_address: TCP socket ListenStream address. See man systemd.socket for format. Default is unset.

libvirt_host_tls_listen: Indicates if the TLS socket unit should be enabled via systemd. Default is false.

libvirt_host_tls_listen_address: TLS socket ListenStream address. See man systemd.socket for format. Default is unset.

libvirt_host_tls_server_cert: TLS server certificate. Default is unset.

libvirt_host_tls_server_key: TLS server key. Default is unset.

libvirt_host_tls_client_cert: TLS client certificate. Default is unset.

libvirt_host_tls_client_key: TLS client key. Default is unset.

libvirt_host_tls_cacert: TLS CA certificate. Default is unset.

libvirt_host_configure_apparmor: Indicates if AppArmor should be set up for directory storage pools.

Dependencies

None

Example Playbook

---
- name: Ensure that Libvirt is configured
  hosts: all
  roles:
    - role: stackhpc.libvirt-host
      libvirt_host_pools:
        - name: my-pool
          type: dir
          capacity: 1024
          path: /path/to/pool
          mode: 755
          owner: my-user
          group: my-group
        - name: lvm_pool
          type: logical
          source: vg1
          target: /dev/vg1
          pvs:
            - /dev/sda3
        - name: rbd-pool
          type: rbd
          source: rbd
          hosts:
            - 192.168.42.200
            - 192.168.42.204
            - 192.168.42.208
          username: admin
          passphrase: xxxxxxxxxxxxxxxxxxxxxxxxxxxxx

      libvirt_host_networks:
        - name: br-example
          mode: bridge
          bridge: br-example
        - name: brnat-example
          mode: nat
          bridge: brnat-example
          domain: example.local
          ip: 192.168.133.254
          netmask: 255.255.255.0
          dhcp_start: 192.168.133.100
          dhcp_end: 192.168.133.200

Author Information

• Mark Goddard (mark@stackhpc.com)