200 | Chapter 12 - IPX Filtering |
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IPX Packet Filter Options
The basic action specified in the rule will almost always be accompanied with an option. IPX Packet filter options use some or all of a set of operators to determine whether the filter rule matches information in a packet or not. These operators are discussed below:
•eq, ==, or = These are allowable ways of writing an “equality” operator which will match if the value in the packet is equal to the value specified in the option expression.
•lt or < These are allowable ways of writing a “less than” operator which will match a packet if its value is less than the value specified in the option expression.
•lteq, le, <=, or =< These are allowable ways of writing a “less than or equal to” operator which will match a packet if its value is less than or equal to the value specified in the option expression.
•gt or > These are allowable ways of writing a “greater than” operator which will match a packet if its value is greater than the value specified in the option expression.
•gteq, ge, >=, or => These are allowable ways of writing a “greater than or equal to” operator which will match a packet if its value is greater than or equal to the value specified in the option expression.
•ne, <>, or != These are allowable ways of writing an “inequality” oper- ator which will match if the value in the packet is not equal to the value specified in the option expression.
ϖNote: In rules where expressions are used, the syntax checker requires a space before and a space after the expression operator(s).
The options available for IPX Packet filter rules allow rules to be more narrowly specified to exclude all but certain types of packets, packets with a given source network number (srcnet), packets with a specified destination network numbers (dstnet), packets with a particular source socket number (srcskt), packets with a selected destination socket number (dstskt), packets with a chosen source node address (srcnode), and/or packets with a stated destination node address (dstnode).
•type <operator> <IPX packet type> This option allows filtering using the IPX packet type contained in the packet. The IPX packet type value must be a hex number. The keyword all may be used to specify all network number values.
For some versions of NetWare, the packet type field is not a reliable indi- cator of the type of packet encapsulated by the IPX header. Generally, the