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From: Reindl Harald <h.reindl@thelounge.net>
To: Daniel <tech@tootai.net>, netfilter@vger.kernel.org
Subject: Re: NAT - how external source port is selected
Date: Wed, 18 Aug 2021 17:15:29 +0200	[thread overview]
Message-ID: <e8eda3b8-0870-7971-b537-e83525e90c02@thelounge.net> (raw)
In-Reply-To: <30dceaf1-7087-2f80-800d-129d6e0dcb59@tootai.net>



Am 18.08.21 um 16:50 schrieb Daniel:
> How is the magic done then ?

which magic?

a tuple is "src-ip:src-port dst-ip:dst-port" and as long there is no 
collision it's 1:1, if there is a collison a random port is used - 
that's what conntrack is for

you don't need to care on a nat router

> Le 18/08/2021 à 16:22, Reindl Harald a écrit :
>>
>>
>> Am 18.08.21 um 15:53 schrieb Daniel:
>>> how on a NAT firewall server using iptables or nftables, are the 
>>> external source ports choosen?
>> NAT don't chose any ports at all

  reply	other threads:[~2021-08-18 15:15 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-18 13:53 NAT - how external source port is selected Daniel
2021-08-18 14:22 ` Reindl Harald
2021-08-18 14:50   ` Daniel
2021-08-18 15:15     ` Reindl Harald [this message]
2021-08-18 14:46 ` Florian Westphal
2021-08-18 15:12   ` Daniel
     [not found]     ` <20210818161622.GS607@breakpoint.cc>
2021-08-18 16:43       ` Daniel
2021-08-18 14:52 ` AW: " Thomas Bätzler

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