Multi-table iptables Question

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# 1  
Old 08-03-2014
Multi-table iptables Question

I have a question regarding IPTables packet flow, that I am hoping I can get an answer to.

We have a fairly advanced implementation of IPTables that I am trying to convert into a third party product and I am not quite certain on the packet flow in the current IPTables implementation.

We are using Mangle, NAT and Filter tables - and my question is this:

We have a PREROUTING chain defined in Mangle AND NAT tables. If a rule is matched with a -j of ACCEPT in the Mangle PREROUTING chain, does the packet still flow to the NAT PREROUTING chain? Or does it just go to the FORWARD chain and skip any other PREROUTING chains in other tables?

That is the missing piece of logic in my head and I would love to have that answered, thank you.
# 2  
Old 08-05-2014
I don't have experience with an IPTABLES configuration that is complex enough to test this. However I can read. It says here "ACCEPT target This built-in target discontinues processing of the current chain and goes to the next table and chain in the standard flow." This is from the book LINUX iptables Pocket Reference.
# 3  
Old 08-05-2014
The information here may help make sense of it.
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