All accounts, by default, have a preconfigured set of thresholds, or limits, to manage capacity and prevent abuse of the system. The system recognizes two kinds of limits: rate limits and absolute limits. Rate limits are thresholds that are reset after a certain amount of time passes. Absolute limits are fixed. Rate limits are processed via the Repose service.
Rate limits control the frequency at which the user can issue specific API requests. Limits can be applied to any of the following entities, depending on the data available in the operation request.
- IP address submitting the request.
- user name
- token sent in the
X-Auth-Tokenheader
If a requester exceeds the rate limit, the request is rejected with a 413 overLimit error. Typically, the request can be resubmitted in a few seconds.
If the client requests continue to be rejected, check the client, process, or application code to verify that API access is managed effectively. Make sure that client applications follow best practices for managing tokens.
The Identity service has its own rate limiting settings, and so does each node. These settings are managed by the Rackspace operations team. If an application node is restarted, the last properties set for any of the Identity service versions are loaded to all nodes.
Note
If the default limits are too low for your particular application, contact Rackspace Cloud support to request an increase. All requests require reasonable justification.