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I'm using "-A INPUT -j LOG" as my last rule to see packets coming in other than what my firewall rules allow. The logging works, but it doesn't tell me what port numbers are being connected to. How do I get this information so I can identify where these packets are coming from?

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up vote 3 down vote accepted

Sure it does, your logs should look like this. You want to look at the SPT, and DPT for the source and destination ports.

Sep 18 06:27:25 fw-01 kernel: [12289826.560795] ''IN-IfAll':'IN=vlan0020 OUT= MAC=00:19:b9:f9:bd:14:00:0b:db:95:b1:d6:08:00 SRC= DST= LEN=76 TOS=0x00 PREC=0x00 TTL=110 ID=10385 PROTO=UDP SPT=295 DPT=123 LEN=56

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Ah! Bone head moment. The port numbers were so large I missed it. Thanks! – Luke Sep 23 '11 at 20:05

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