OpenFlow custom pipeline implementation notes

OpenFlow Table modifications cannot be done in v1/v2 modules or on v3 modules in compatibility mode.

When the instance is configured in Standard match mode or ip-control-table-mode, controllers cannot change the default pipeline advertised by controller.

For IPv6 packets, MAC SA modification is not allowed. L4 ports modifications are not allowed for IPv6 packets.

Write-metadata instructions are not supported.

Rules with actions as packet-modifications and OFPP_CONTROLLER are directly rejected. However, if the rules span across multiple tables (write-instruction in first table having packet modifications and write-instructions in further tables having OFPP_CONTROLLER) would be accepted – however, the packets taken to CPU/CONTROLLER are unmodified.

Special ports OFPP_ALL, OFPP_LOCAL, OFPP_TABLE, and OFPP_IN_PORT are not supported.

Write-instruction having OFPP_CONTROLLER cannot have a Goto instruction associated with it.

Write-instruction rules must always have output port specified or Goto to next table or “output port + goto”.

Counters are associated with tables and flow entries if available. Otherwise, the table or flow creation is rejected with an error Resources not available to the controller.

Tables configured from the controller must have a minimum of 512 entries or the table creation request is rejected.

Before a table is deleted, the controller must remove all flows in previous tables pointing to the deleted table. If all flows are not removed, the controller table modification (deletion/modification) is not allowed.

For multiple custom-pipeline instances, the user must reduce the size of the tables in the first custom-pipeline instance. Following this procedure, the user must disable and enable the other custom-match instances for them to become operational.