nova compute #0

Supports: xenial bionic artful trusty


OpenStack Compute, codenamed Nova, is a cloud computing fabric controller. In addition to its "native" API (the OpenStack API), it also supports the Amazon EC2 API. . This charm provides the Nova Compute hypervisor service and should be deployed directly to physical servers.


This charm provides Nova Compute, the OpenStack compute service. Its target platform is Ubuntu (preferably LTS) + OpenStack.


The following interfaces are provided:

  • cloud-compute - Used to relate (at least) with one or more of nova-cloud-controller, glance, ceph, cinder, mysql, ceilometer-agent, rabbitmq-server, neutron

  • nrpe-external-master - Used to generate Nagios checks.


Nova compute only requires database access if using nova-network. If using Neutron, no direct database access is required and the shared-db relation need not be added.


This charm support nova-network (legacy) and Neutron networking.


This charm supports a number of different storage backends depending on your hypervisor type and storage relations.

In order to have cinder ceph rbd support for Openstack Ocata and newer releases, ceph-access relation must be added to cinder-ceph to allow nova-compute units to communicate with multiple ceph backends using different cephx keys and user names.

$ juju add-relation nova-compute cinder-ceph

See LP Bug #1671422 for more information.

NFV support

This charm (in conjunction with the nova-cloud-controller and neutron-api charms) supports use of nova-compute nodes configured for use in Telco NFV deployments; specifically the following configuration options (yaml excerpt):

  hugepages: 60%
  vcpu-pin-set: "^0,^2"
  reserved-host-memory: 1024
  pci-passthrough-whitelist: {"vendor_id":"1137","product_id":"0071","address":"*:0a:00.*","physical_network":"physnet1"}

In this example, compute nodes will be configured with 60% of available RAM for hugepage use (decreasing memory fragmentation in virtual machines, improving performance), and Nova will be configured to reserve CPU cores 0 and 2 and 1024M of RAM for host usage and use the supplied PCI device whitelist as PCI devices that as consumable by virtual machines, including any mapping to underlying provider network names (used for SR-IOV VF/PF port scheduling with Nova and Neutron's SR-IOV support).

The vcpu-pin-set configuration option is a comma-separated list of physical CPU numbers that virtual CPUs can be allocated to by default. Each element should be either a single CPU number, a range of CPU numbers, or a caret followed by a CPU number to be excluded from a previous range. For example:

vcpu-pin-set: "4-12,^8,15"

The pci-passthrough-whitelist configuration must be specified as follows:

A JSON dictionary which describe a whitelisted PCI device. It should take the following format:

["device_id": "<id>",] ["product_id": "<id>",]
["address": "[[[[<domain>]:]<bus>]:][<slot>][.[<function>]]" |
"devname": "PCI Device Name",]
{"tag": "<tag_value>",}

where '[' indicates zero or one occurrences, '{' indicates zero or multiple occurrences, and '|' mutually exclusive options. Note that any missing fields are automatically wildcarded. Valid examples are:

pci-passthrough-whitelist: {"devname":"eth0", "physical_network":"physnet"}

pci-passthrough-whitelist: {"address":"*:0a:00.*"}

pci-passthrough-whitelist: {"address":":0a:00.", "physical_network":"physnet1"}

pci-passthrough-whitelist: {"vendor_id":"1137", "product_id":"0071"}

pci-passthrough-whitelist: {"vendor_id":"1137", "product_id":"0071", "address": "0000:0a:00.1", "physical_network":"physnet1"}

The following is invalid, as it specifies mutually exclusive options:

pci-passthrough-whitelist: {"devname":"eth0", "physical_network":"physnet", "address":"*:0a:00.*"}

A JSON list of JSON dictionaries corresponding to the above format. For example:

pci-passthrough-whitelist: [{"product_id":"0001", "vendor_id":"8086"}, {"product_id":"0002", "vendor_id":"8086"}]`

The OpenStack advanced networking documentation provides further details on whitelist configuration and how to create instances with Neutron ports wired to SR-IOV devices.


(string) Experimental enable apparmor profile. Valid settings: 'complain', 'enforce' or 'disable'. . AA disabled by default.
(boolean) If True enables openstack upgrades for this charm via juju actions. You will still need to set openstack-origin to the new repository but instead of an upgrade running automatically across all units, it will wait for you to execute the openstack-upgrade action for this charm on each unit. If False it will revert to existing behavior of upgrading all units on config change.
(string) Only used when migration-auth-type is set to ssh. . Full path to authorized_keys file, can be useful for systems with non-default AuthorizedKeysFile location. It will be formatted using the following variables: . homedir - user's home directory username - username .
(string) Bridge interface to be configured.
(string) IP to be assigned to bridge interface.
(string) Netmask to be assigned to bridge interface.
(int) This value dictates the number of replicas ceph must make of any object it stores within the nova rbd pool. Of course, this only applies if using Ceph as a backend store. Note that once the nova rbd pool has been created, changing this value will not have any effect (although it can be changed in ceph by manually configuring your ceph cluster).
(int) Defines a relative weighting of the pool as a percentage of the total amount of data in the Ceph cluster. This effectively weights the number of placement groups for the pool created to be appropriately portioned to the amount of data expected. For example, if the ephemeral volumes for the OpenStack compute instances are expected to take up 20% of the overall configuration then this value would be specified as 20. Note - it is important to choose an appropriate value for the pool weight as this directly affects the number of placement groups which will be created for the pool. The number of placement groups for a pool can only be increased, never decreased - so it is important to identify the percent of data that will likely reside in the pool.
(string) Comma-separated list of key=value config flags. These values will be placed in the nova.conf [DEFAULT] section.
(string) Set to 'host-model' to clone the host CPU feature flags; to 'host-passthrough' to use the host CPU model exactly; to 'custom' to use a named CPU model; to 'none' to not set any CPU model. If virt_type='kvm|qemu', it will default to 'host-model', otherwise it will default to 'none'. Defaults to 'host-passthrough' for ppc64el, ppc64le if no value is set.
(string) Set to a named libvirt CPU model (see names listed in /usr/share/libvirt/cpu_map.xml). Only has effect if cpu_mode='custom' and virt_type='kvm|qemu'.
(string) Nova database name.
(string) Username for database access.
(boolean) Enable debug logging.
(string) Default compute node availability zone. . This option determines the availability zone to be used when it is not specified in the VM creation request. If this option is not set, the default availability zone 'nova' is used. . NOTE: Availability zones must be created manually using the 'openstack aggregate create' command. .
(string) Specific cachemodes to use for different disk types e.g: file=directsync,block=none
(boolean) Configure libvirt or lxd for live migration. . Live migration support for lxd is still considered experimental. . NOTE: This also enables passwordless SSH access for user 'root' between compute hosts.
(boolean) Enable instance resizing. . NOTE: This also enables passwordless SSH access for user 'nova' between compute hosts.
(string) Network interface on which to build bridge.
(boolean) Force conversion of backing images to raw format. Note that the conversion process in Pike uses O_DIRECT calls - certain file systems do not support this, for example ZFS; e.g. if using the LXD provider with ZFS backend, this option should be set to False.
(string) Apply system hardening. Supports a space-delimited list of modules to run. Supported modules currently include os, ssh, apache and mysql.
(string) The percentage of system memory to use for hugepages eg '10%' or the total number of 2M hugepages - eg "1024". For a systemd system (wily and later) the prefered approach is to enable hugepages via kernel parameters set in MAAS and systemd will mount them automatically. . NOTE: For hugepages to work it must be enabled on the machine deployed to. This can be accomplished by setting kernel parameters on capable machines in MAAS, tagging them and using these tags as constraints in the model.
(string) Path used for storing Nova instances data - empty means default of /var/lib/nova/instances.
(string) Set to 1 to enable KSM, 0 to disable KSM, and AUTO to use default settings. . Please note that the AUTO value works for qemu 2.2+ (> Kilo), older releases will be set to 1 as default.
(string) Tell Nova which libvirt image backend to use. Supported backends are rbd, lvm and qcow2. If no backend is specified, the Nova default (qcow2) is used. Note that rbd imagebackend is only supported with >= Juno.
(string) TCP authentication scheme for libvirt live migration. Available options include ssh.
(string) Whether to run nova-api and nova-network on the compute nodes.
(string) Used by the nrpe-external-master subordinate charm. A string that will be prepended to instance name to set the host name in nagios. So for instance the hostname would be something like: . juju-myservice-0 . If you're running multiple environments with the same services in them this allows you to differentiate between them.
(string) A comma-separated list of nagios servicegroups. If left empty, the nagios_context will be used as the servicegroup.
(string) Full path to Nova configuration file.
(string) Repository from which to install. May be one of the following: distro (default), ppa:somecustom/ppa, a deb url sources entry or a supported Ubuntu Cloud Archive (UCA) release pocket. . Supported UCA sources include: . cloud:<series>-<openstack-release> cloud:<series>-<openstack-release>/updates cloud:<series>-<openstack-release>/staging cloud:<series>-<openstack-release>/proposed . For series=Precise we support UCA for openstack-release= * icehouse . For series=Trusty we support UCA for openstack-release= * juno * kilo * ... . NOTE: updating this setting to a source that is known to provide a later version of OpenStack will trigger a software upgrade. .
(string) The IP address and netmask of the OpenStack Internal network (e.g. . This network will be used to bind vncproxy client.
(string) Sets the pci_passthrough_whitelist option in nova.conf which allows PCI passthrough of specific devices to VMs. . Example applications: GPU processing, SR-IOV networking, etc. . NOTE: For PCI passthrough to work IOMMU must be enabled on the machine deployed to. This can be accomplished by setting kernel parameters on capable machines in MAAS, tagging them and using these tags as constraints in the model.
(boolean) If True enables IPv6 support. The charm will expect network interfaces to be configured with an IPv6 address. If set to False (default) IPv4 is expected. . NOTE: these charms do not currently support IPv6 privacy extension. In order for this charm to function correctly, the privacy extension must be disabled and a non-temporary address must be configured/available on your network interface.
(string) Username used to access rabbitmq queue.
(string) Rabbitmq vhost.
(string) Enable/disable rbd client cache. Leaving this value unset will result in default Ceph rbd client settings being used (rbd cache is enabled by default for Ceph >= Giant). Supported values here are "enabled" or "disabled".
(string) RBD pool to use with Nova libvirt RBDImageBackend. Only required when you have libvirt-image-backend set to 'rbd'.
(int) Amount of memory in MB to reserve for the host. Defaults to 512MB.
(boolean) Optionally restrict Ceph key permissions to access pools as required.
(boolean) This option determines whether to start guests that were running before the host rebooted.
(string) YAML formatted associative array of sysctl values, e.g.: '{ kernel.pid_max : 4194303 }'
(boolean) Openstack mostly defaults to using public endpoints for internal communication between services. If set to True this option will configure services to use internal endpoints where possible.
(boolean) Use a multipath connection for iSCSI volumes.
(boolean) Setting this to True will allow supporting services to log to syslog.
(string) Sets vcpu_pin_set option in nova.conf which defines which pcpus that instance vcpus can or cannot use. For example '^0,^2' to reserve two cpus for the host.
(boolean) Enable verbose logging.
(string) Virtualisation flavor. Supported and tested flavors are: kvm, lxd. If using the lxd flavor, the lxd subordinate charm must also be related. Other native libvirt flavors available to exercise (dev/test only): uml, lxc, qemu. NOTE: Changing virtualisation flavor after deployment is not supported.
(float) The CPU core multiplier to use when configuring worker processes for this services e.g. metadata-api. By default, the number of workers for each daemon is set to twice the number of CPU cores a service unit has. When deployed in a LXD container, this default value will be capped to 4 workers unless this configuration option is set.