Observer Matrix : Matrix CLI : Matrix CLI : help filter
   
help filter
The command help filter briefly describes the Berkeley Packet Filter (BPF) syntax and the custom extensions for it.
A BPF expression consists of one or more primitives. A primitive consists of an id (value) preceded by one or more qualifiers. There are three types of qualifiers. They are listed in the order in which they must appear in an expression.
Filter expressions can be combined using logic operators: and, &&,or,||,not, !. and and or have equal precedence and are evaluated from left to right . Negation (!, not) has the highest precedence. Expressions can be logically grouped using parenthesis (, ).
Identical qualifier lists can be omitted to shorten the expression. For example ip src host 1.2.3.4 or ip src host 1.2.3.5 can be written as ip src host 1.2.3.4 or 1.2.3.5.
For more details about the BPF syntax, see http://biot.com/capstats/bpf.html. The syntax has been extended in the following ways:
Added support for protocol: sctp, tcpdata, and udpdata.
Added types: hostnet and netport.
Removed support for protocols: fddi, tr, wlan and decnet.
Removed support for: atalk, aarp, decnet, iso, stp, ipx, and netbeui.
These primitives do not conform to the standard pattern: broadcast, less, greater, len, multicast, and data accessors.
These primitives are not supported: gateway, protochain, decnet, ifname, on, rnr, rulenum, reason, rst, ruleset, srnr, subrulenum, action, pppoed, pppoes, iso proto, vpi, vci, lane, llc, oamf4s, oamf4e, oamf4, oam, metac, bcc, sc, ilmic, connectmsg, and metaconnect.
 
Usage
help filter
 
 
Examples
matrix_host> help filter