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Old 08-11-2014, 02:09 AM   #1
D0zer
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Blocking p2p traffic with Iptables on Gentoo


Hi All

I have been battling with slow internet at a client. At first I thought squid was the culprit, then possible the load balancing on the 2 lines. After some more research it could be p2p traffic causing issues. Bellow is the TX, RX, and Total output on jnettop for eth0 and eth2

Eth0 : TX 4.85k/s, RX 22.9k/s Total 27.8k/s
Eth2 : TX 135k/s, RX 96.3k/s Total 231k/s

Noticing lots of high numbered ports for tcp and udp. http, https, smtp, pop3 should be majority of the traffic. Any recommendations of what I can use to block traffic that should not be on the network?

Thanks

Last edited by D0zer; 08-11-2014 at 02:15 AM. Reason: Changed the Jenttop information
 
Old 08-15-2014, 09:44 AM   #2
D0zer
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I'm still looking for ways to block peer to peer downloads, and for a way of shaping traffic for the local network. I had the adsl line fixed today and the internet is working like a dream. I updated squid and re configured it, browsing is much better now. Squid was not giving timeout errors when browsing. I suspect all the issues where because the one line was not working correctly and routing through the eth2 was not working correctly.
 
Old 08-17-2014, 05:44 PM   #3
unSpawn
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Quote:
Originally Posted by D0zer View Post
I'm still looking for ways to block peer to peer downloads, and for a way of shaping traffic for the local network.
Did you analyse your logs / stats to find clues what to block? What research have you done wrt traffic shaping?
 
Old 08-17-2014, 05:55 PM   #4
brebs
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Here's some hints, at least.
 
Old 08-18-2014, 05:37 AM   #5
D0zer
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Thank's for the link brebs. looks like what I am looking for.
Quote:
Originally Posted by brebs View Post
Here's some hints, at least.
 
Old 08-18-2014, 05:43 AM   #6
D0zer
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Thank's for the reply unSpawn. I haven't done much research into traffic shaping yet. I am hoping to spend some time today on it.

I view the jnettop utility, but I am still getting use to understanding it. Have you got any suggestions what log files I should be monitoring, and if I should turn any other's on? I tried to use ntop to get an overview of things, but I see it seems to have crashed again when I went to check it.

Quote:
Originally Posted by unSpawn View Post
Did you analyse your logs / stats to find clues what to block? What research have you done wrt traffic shaping?
 
Old 08-18-2014, 05:01 PM   #7
unSpawn
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Quote:
Originally Posted by D0zer View Post
Thank's for the reply unSpawn. I haven't done much research into traffic shaping yet. I am hoping to spend some time today on it.
If you want to go the "easy" way search for the "wonder shaper" script (should be in LARTC, IIRC), if you want to understand the whole thing search for LARTC.


Quote:
Originally Posted by D0zer View Post
I view the jnettop utility, but I am still getting use to understanding it. Have you got any suggestions what log files I should be monitoring, and if I should turn any other's on? I tried to use ntop to get an overview of things, but I see it seems to have crashed again when I went to check it.
Ntop can be somewhat unstable (I'm sure that's an understatement). It kind of depends where you check. If the gateway runs iptables you could just log new outbound connections ("-m state --state NEW") for say twentyfour hours and then see what remote ports get hit and how many times. If it doesn't run iptables but you can run tcpdump (or via SPAN) you could save packet captures and run them on your workstation through command line analysis tools or Wireshark. Do note that might take up lots of space so use a BPF filter. If it can't do none of that tell us what it can provide.
 
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Old 08-19-2014, 12:32 PM   #8
D0zer
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Thanks for the help so far unSpawn
 
  


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