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On 3/2/07, Daniel Iliev <danny@××××××××.com> wrote: |
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> |
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> CapSel wrote: |
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> > On 3/1/07, *Boyd Stephen Smith Jr.* <bss03@××××××××××.net |
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> > <mailto:bss03@××××××××××.net>> wrote: |
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> > |
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> > That would be correct, since every forwarded packet passes though |
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> > both the |
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> > pre-routing and post-routing chains, so you are counting every |
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> > packet (at |
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> > least those that are not dropped in the FORWARD chain) twice. |
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> > |
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> > |
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> > I don't fully understand how is that possible that my rules count |
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> > packet twice, could you explain it more briefly? |
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> > |
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> > I specified -i eth0 in PREROUTING and -o eth0 in POSTROUTING. Isn't |
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> > this correct way to count packets only once? ...and I'm getting values |
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> > only from chain 'stat', which is called only from PREROUTING and |
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> > POSTROUTING with specified network interface respectively to direction |
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> > (-i/-o eth0). |
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> > So in my opinion a packet traveling through the router to my network |
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> > passes only once through 'stats' as it is accepted only in PREROUTING |
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> > with -i eth0, and not in POSTROUTING with -o eth0, as it goes out from |
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> > eth1. Am I correct? |
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> |
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> |
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> Perhaps this packet travel diagram will help: |
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> |
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> http://www.linuxnetmag.com/share/issue9/iptables3.jpg |
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To be totally sure - when packet arrives from internet to eth0 it passes |
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through PREROUTING as packet "that comes from eth0", then it travels across |
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FORWARD as packet "that comes from eth0 toward eth1", and finally it goes to |
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POSTROUTING as packet "that wants to come out through eth1"? And if I have |
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rules: |
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|
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-t mangle -A PREROUTING -i eth0 -j stats |
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-t mangle -A POSTROUTING -o eth0 -j stats |
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(there are no other rules that jumps to stats, and these are only rules in |
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mangle table) |
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how many times the packet would pass through 'stats'? |
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|
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>From witch places on this diagram iptraf takes values? |