Unified Limits Quotas

Since the Nova 28.0.0 (2023.2 Bobcat) release, it is recommended to use Keystone unified limits for Nova quota limits.

For information about legacy quota limits, see the legacy quota documentation.

Nova uses a quota system for setting limits on resources such as number of instances or amount of CPU that a specific project or user can use.

Quota limits are set by admin and retrieved for enforcement using the Keystone API.

Types of quota

Unified limit resource names for resources that are tracked as resource classes in the placement service follow the naming pattern of the class: prefix followed by the name of the resource class. For example: class:VCPU, class:PCPU, class:MEMORY_MB, class:DISK_GB, class:VGPU.

Quota name	Description
class:VCPU	Number of shared CPU cores (VCPUs) allowed per project.
class:PCPU	Number of dedicated CPU cores (PCPUs) allowed per project.
servers	Number of instances allowed per project.
server_key_pairs	Number of key pairs allowed per user.
server_metadata_items	Number of metadata items allowed per instance.
class:MEMORY_MB	Megabytes of instance ram allowed per project.
server_groups	Number of server groups per project.
server_group_members	Number of servers per server group.
class:DISK_GB	Gigabytes of instance disk allowed per project.
class:<any resource class in the placement service>	Any resource class in the placement service that is allocated by Nova can have a quota limit specified for it. Example: class:VGPU.

The following quotas were previously available but were removed in microversion 2.36 as they proxied information available from the networking service.

Quota name	Description
fixed_ips	Number of fixed IP addresses allowed per project. This number must be equal to or greater than the number of allowed instances.
floating_ips	Number of floating IP addresses allowed per project.
networks	Number of networks allowed per project (no longer used).
security_groups	Number of security groups per project.
security_group_rules	Number of security group rules per project.

Similarly, the following quotas were previously available but were removed in microversion 2.57 as the personality files feature was deprecated.

Quota name	Description
injected_files	Number of injected files allowed per project.
injected_file_content_bytes	Number of content bytes allowed per injected file.
injected_file_path_bytes	Length of injected file path.

Usage

Project quotas

To list all default quotas for projects, run:

$ openstack registered limit list

Note

This lists default quotas for all services and not just nova.

For example:

$ openstack registered limit list
+----------------------------------+----------------------------------+------------------------------------+---------------+-------------+-----------+
| ID                               | Service ID                       | Resource Name                      | Default Limit | Description | Region ID |
+----------------------------------+----------------------------------+------------------------------------+---------------+-------------+-----------+
| eeee406035fc4a7892c6fc6fcc76e61a | b5d97619e6354c03be50c6b1589e6547 | image_size_total                   |          1000 | None        | RegionOne |
| b99d35b1b7b74cd0a26a6311963328af | b5d97619e6354c03be50c6b1589e6547 | image_stage_total                  |          1000 | None        | RegionOne |
| 70945789dad24082bc2a8cdbf53a5091 | b5d97619e6354c03be50c6b1589e6547 | image_count_total                  |           100 | None        | RegionOne |
| 908d86c0ac3f46d0bb45ed9194710ea7 | b5d97619e6354c03be50c6b1589e6547 | image_count_uploading              |           100 | None        | RegionOne |
| be6dfeebb7c340e8b93b602d41fbff9b | 8b22bf8a66fa4524a522b2a21865bbf2 | servers                            |            10 | None        | None      |
| 8a658096236549788e61f4fcbd5a4a12 | 8b22bf8a66fa4524a522b2a21865bbf2 | class:VCPU                         |            20 | None        | None      |
| 63890db7d6a14401ba55e7f7022b95d0 | 8b22bf8a66fa4524a522b2a21865bbf2 | class:MEMORY_MB                    |         51200 | None        | None      |
| 221ba1c19d2c4272952663828d659013 | 8b22bf8a66fa4524a522b2a21865bbf2 | server_metadata_items              |           128 | None        | None      |
| 8e61cabd2e854a11bdd2cf94efd702d1 | 8b22bf8a66fa4524a522b2a21865bbf2 | server_injected_files              |             5 | None        | None      |
| 3d259390f70e4e9b88ecb2b0fa075f9b | 8b22bf8a66fa4524a522b2a21865bbf2 | server_injected_file_content_bytes |         10240 | None        | None      |
| a12e10b991cc4bdd8e6ff30f6e6c15ac | 8b22bf8a66fa4524a522b2a21865bbf2 | server_injected_file_path_bytes    |           255 | None        | None      |
| a32a9080be6b4a5481c16a91fe329e6f | 8b22bf8a66fa4524a522b2a21865bbf2 | server_key_pairs                   |           100 | None        | None      |
| 86408bb7a0e542b18404ec7d348da820 | 8b22bf8a66fa4524a522b2a21865bbf2 | server_groups                      |            10 | None        | None      |
| 17c4552c5aad4afca4813f37530fc897 | 8b22bf8a66fa4524a522b2a21865bbf2 | server_group_members               |            10 | None        | None      |
+----------------------------------+----------------------------------+------------------------------------+---------------+-------------+-----------+

To show details about a default limit, run:

$ openstack registered limit show <registered-limit-id>

For example:

$ openstack registered limit show 8a658096236549788e61f4fcbd5a4a12
+---------------+----------------------------------+
| Field         | Value                            |
+---------------+----------------------------------+
| default_limit | 20                               |
| description   | None                             |
| id            | 8a658096236549788e61f4fcbd5a4a12 |
| region_id     | None                             |
| resource_name | class:VCPU                       |
| service_id    | 8b22bf8a66fa4524a522b2a21865bbf2 |
+---------------+----------------------------------+

To list the currently set quota values for your project, run:

$ openstack limit list

For example:

$ openstack limit list
+----------------------------------+----------------------------------+----------------------------------+---------------+----------------+-------------+-----------+
| ID                               | Project ID                       | Service ID                       | Resource Name | Resource Limit | Description | Region ID |
+----------------------------------+----------------------------------+----------------------------------+---------------+----------------+-------------+-----------+
| 8b3364b2241e4090aaaa49355c7a5b56 | 5cd3281595a9497ba87209701cd9f3f2 | 8b22bf8a66fa4524a522b2a21865bbf2 | class:VCPU    |              5 | None        | None      |
+----------------------------------+----------------------------------+----------------------------------+---------------+----------------+-------------+-----------+

To show details about a quota limimt, run:

$ openstack limit show <limit-id>

For example:

$ openstack limit show 8b3364b2241e4090aaaa49355c7a5b56
+----------------+----------------------------------+
| Field          | Value                            |
+----------------+----------------------------------+
| description    | None                             |
| domain_id      | None                             |
| id             | 8b3364b2241e4090aaaa49355c7a5b56 |
| project_id     | 5cd3281595a9497ba87209701cd9f3f2 |
| region_id      | None                             |
| resource_limit | 5                                |
| resource_name  | class:VCPU                       |
| service_id     | 8b22bf8a66fa4524a522b2a21865bbf2 |
+----------------+----------------------------------+