Compatible Systems 5.4 用户手册
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Chapter 12 - IPX Filtering
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:
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.
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.
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.
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.
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.
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.
ator which will match if the value in the packet is not equal to the value
specified in the option expression.
v Note: In rules where expressions are used, the syntax checker requires a
space before and a space after the expression operator(s).
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).
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.
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
cator of the type of packet encapsulated by the IPX header. Generally, the