Net Optics none Network Router User Manual


 
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Director
Create Filters
Filters process a trafc stream by selecting packets based on criteria in the packet header. A lter is dened using a
lteraddcommand, which also species the Network ports and Monitor ports the lters apply to. The lteradd
command species the following behavior:
Trafc is aggregated from all the listed Network ports
Then the lter parameters are applied
Packets which match all of the specied lter parameters are copied to all of the listed Monitor ports, assuming
the action=redir.
If the action=drop, the matching packets are not copied to any Monitor port; this mechanism is used to create
exclusive lters.
TosendMonitorPort1alltrafcreceivedatNetworkPort5fromIPaddresses192.168.10.0 to 192.168.10.15:
Enter 1. lteraddin_ports=n1.5ip_src=192.168.10.0ip_src_mask=240action=redirredir_ports=m.1. A lter
has been dened to select all IPv4 packets from Network Port 5 with a source IP addresses of 192.168.10.0 and the
lowest four address bits masked out (ignored); packets matching the lter are copied to Monitor Port 1.
Enter 2. ltercommit. The lter is activated.
Network Port 5 Monitor Port 1
Source IP =
192.168.10.0 –
192.168.10.15
lter add in_ports=n1.5 ip_src=192.168.10.0 ip_src_mask= 240 action=redir redir_ports=m.1
Simple IP address lterFigure 26:
TocreatealterthatselectsIPv4packetsbyprotocol:
Enter 1. lteraddin_ports=n1.3ip4_prot=3action=redirredir_ports=m.6,m.8. A lter has been dened to select
all IPv4 packets that use the TCP protocol received at Network Port 3 and copy them to Monitor Port 6 and Monitor
Port 8. (Protocols are designated by an industry-standard numbering system. See Appendix C for details.)
Enter 2. ltercommit. The lter is activated.
Network Port 3
Protocol =
TCP
Monitor Port 6
Monitor Port 8
lter add in_ports=n1.3 ip4_prot=3 action=redir redir_ports=m.6,m.8
Simple IPv4 protocol lter (with regeneration)Figure 27:
Available lter parameters are listed in Appendix B and include:
ip_src IP source address
ip_src_mask IP destination address mask