Quota Management

Resouce quotas can be set in an OpenStack environment to ensure that we do not unintentionally exhaust the capacity. In OpenStack quotas can be set to give each resource some operational limit.

Quotas are checked in the follwing order:

Project specific limit

If set for a specific resource this limit will be used first. Exmaple, for a project we can set quotas for any resource like so:

  openstack quota set --cores 100 <project>

Default limits

These are hard limit set the database under quota_classes for the default quota class. If project sepcific limit is not set for a given resource and default limit is set, OpenStack uses this limit.

To set a default limit for a resource:

  openstack quota set --cores 120 default

Note

Once the default limit is set via the API, it takes precedence over config limits. Once it is set, we can only modify the limit, but it can not be deleted via the API. It can however be deleted manually from the database.

Config provided limits

We can set limits on resource through the config file under the quota config group.

Useful quota commands

Show the default quota

  openstack quota show --default

Show quota for a project

  openstack quota show <project>

Update quota for resource instance in default class

  openstack quota set --instances 15 default

Update quota for a resource for a project

  openstack quota set --instances 20 <project>

Note

Quotas class has been replaced with a new driver unified limits. Please see OpenStack docs for unified limits.