Nova Compute

juju deploy nova-compute

20.10 20.04 LTS 19.10 18.04 LTS 16.04 LTS 14.04 LTS

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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. The nova-network feature is not available in Ussuri and later, and so this interface produces a warning if 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.

Availability Zones

There are two options to provide default_availability_zone config for nova nodes:

  • default-availability-zone
  • customize-failure-domain

The order of precedence is as follows:

  1. Information from a Juju provider (JUJU_AVAILABILITY_ZONE) if customize-failure-domain is set to True and Juju has set the JUJU_AVAILABILITY_ZONE to a non-empty value;
  2. The value of default-availability-zone will be used if customize-failure-domain is set to True but no JUJU_AVAILABILITY_ZONE is provided via hook context by the Juju provider;
  3. Otherwise, the value of default-availability-zone charm option will be used.

The default_availability_zone in Nova affects scheduling if a given Nova node was not placed into an aggregate with an availability zone present as a property by an operator. Using customize-failure-domain is recommended as it provides AZ-aware scheduling out of the box if an operator specifies an AZ during instance creation.

These options also affect the AZ propagated down to networking subordinates which is useful for AZ-aware Neutron agent scheduling.

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.

Network Spaces

This charm supports use of network spaces by binding relation endpoints.

In addition this charm declares two extra-bindings:

  • internal: this binding is used to determine the network space to use for console access to instances.

  • migration: this binding is used to determine which network space should be used for live and cold migrations between hypervisors.

Note that the nova-cloud-controller application must have bindings to the same network spaces used for both 'internal' and 'migration' extra bindings.

See the Juju documentation for more information on using network spaces.