Known limitations

Contributors dmp-netapp

The ONTAP REST API has certain limitations or restrictions that might affect your use of the API and development of automation code. These restrictions are described below. In general, each applies to all supported ONTAP releases where the REST API is available. See the ONTAP releases field for more information.

Note The REST API first became available with ONTAP 9.6.
REST API requests rejected when input queue is full

ONTAP releases: All supported

Every REST API client request is received by ONTAP and placed in an input queue before being processed. At times of extremely high arrival rates, the input wait queue holding these API requests can temporarily fill up. When this occurs, each additional overflow request is rejected. In these situations:

  • ONTAP recognizes the incoming connection exceeds the wait queue depth and logs a message that it is failing the connection.

  • The REST client observes the failed connection, although the exact behavior can depend on the client. For example, with an NMSDK client the message "Failed to connect to SSL" is presented.

The REST API input wait queue filling up is a rare event. But rejecting the excess requests provides protection against DOS attacks.