[Nelug] iptables doing unwanted logging

James Barton james.barton at blueyonder.co.uk
Tue Aug 12 13:18:01 UTC 2003

Hi all,
I'm probably doing something really dumb here, but if you could point it
out, I'll wear my dunce hat without complaining.

I noticed that syslog has a lot of stuff from iptables in it, and I don't
think it should be there. I've attached my firewall script, it's
definitely running on the gateway, and it clears all existing rules when
it starts.

Since I was ssh'd into the server, most of the lines I saw in syslog were
connections into the machine from my workplace, looking like this:

Aug 12 13:13:54 gateway kernel: IN=eth0 OUT=
MAC=00:20:18:3b:71:b8:00:30:80:93:6b:70:08:00 SRC=
DST= LEN=92 TOS=0x00 PREC=0x00 TTL=123 ID=54309 DF PROTO=TCP
SPT=62528 DPT=22 WINDOW=64240 RES=0x00 ACK PSH URGP=0

Now I think they should have been caught by this rule (the variables for
the name and the IP address do have the right values):

--dport 20:24 -j ACCEPT

and hence not logged. What have I missed?

The only logging done explicitly in the script is by the 'worry' chain,
and all packets sent through that chain are dropped. Since I can actually
use an SSH connection, this can't be happening. Is there some implicit
logging that I haven't turned off?

Any help appreciated,
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