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Explanation | The full list of which filters are defined for a port. These are the sub-index values that are used for the parameters defining the compound conditions on the match/length terms operating on the packets received for the port.
Setting the value of this parameter creates a new empty filter for each value that is not already in use, and deletes each filter that is not mentioned in the list. The same can be accomplished one-filter-at-a-time using the PF_CREATE and PF_DELETE commands. |

fid: | integer, the sub-index of a filter definition for the port. |

Summary | set and get, value types: I* |

Example, set or get: | 0/1 PF_INDICES 0 3 |

Explanation | Creates an empty filter definition with the specified sub-index value. |

fid: | integer, the sub-index value of the filter definition to create. |

Summary | set only, filter index. |

Example, set or get: | 0/1 PF_CREATE [3] |

Explanation | Deletes the filter definition with the specified sub-index value. |

fid: | integer, the sub-index value of the filter definition to delete. |

Summary | set only, filter index. |

Example, set: | 0/1 PF_DELETE [3] |

Explanation | Whether a filter is currently active on a port.
While a filter is enabled its condition cannot be changed, nor can any match term or length terms used by it. |

fid: | integer, the sub-index value of the filter definition. |

onoff: | coded integer, whether the filter is enabled: OFF ON |

Summary | set and get, filter index, value types: B |

Example, set or get: | 0/1 PF_ENABLE [3] OFF |

Explanation | The description of a filter. |

fid: | integer, the sub-index value of the filter definition. |

comment: | string, containing the description of the filter. |

Summary | set and get, filter index, value types: S |

Example, set or get: | 0/1 PF_COMMENT [3] ”Filter for …” |

Explanation | The boolean condition on the terms specifying when the filter is satisfied. The condition uses a cannonical and-or–not expression on the match terms and length terms. The condition is specified using a number of compound terms, each encoded as an integer value specifying an abitrary set of the match terms and length terms defined for the port. Each match/length term has a specific power-of-two value, and the set is encoded as the sum of the values for the contained terms:
Value for match term [mid] = 2 ^ mid Value for length term [lid] = 2 ^ (lid+16)
A compound term is true if all the match terms and length terms contained in it are true. This supports the and-part of the condition. If some compound term is satisfied, the condition as a whole is true. This is the or-part of the condition.
The first few compound terms at the even positions (second, fourth, …) are inverted, and all the contained match terms and length terms must be false at the same time that the those of the preceding compound term are true. This is the not-part of the condition.
In practice, the simplest way to generate these encodings is to use the Manager, which supports Boolean expressions using the operators &, |, and ~, and simply query the chassis for the resulting script-level definition. |

fid: | integer, the sub-index value of the filter definition. terms: integer, encoding a compound term which is a set of the match terms and length terms. |

Summary | set and get, filter index, value types: I* |

Example, set or get: | 0/1 PF_CONDITION [3] |

Explanation | Multi-parameter query, obtaining all the parameters for a specific filter. |

fid: | integer, the sub-index value of the filter definition. |

Summary | get only, filter index. |

Example, get: | 0/1 PF_COMMENT [3] ”Filter for …” 0/1 PF_CONDITION [3] 0/1 PF_ENABLE [3] OFF |

Explanation | Multi-parameter query, obtaining all parameters for all filters defined on a port. |

Summary | get only. |

Example, get: | 0/1 PF_INDICES 0 3 0/1 PF_COMMENT [0] ”Filter for …” . . 0/1 PF_COMMENT [3] ”Filter for …” 0/1 PF_CONDITION [3] 0/1 PF_ENABLE [3] OFF |