From: WGH <wgh@torlan.ru>
To: Patrick McHardy <kaber@trash.net>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>,
Phil Oester <kernel@linuxace.com>,
netfilter-devel@vger.kernel.org
Subject: Re: conntrack, idle TCP connection and keep-alives
Date: Sun, 27 Oct 2013 23:23:17 +0400 [thread overview]
Message-ID: <526D6825.2090505@torlan.ru> (raw)
In-Reply-To: <20131027192019.GD32366@macbook.localnet>
On 27.10.2013 23:20, Patrick McHardy wrote:
> On Sun, Oct 27, 2013 at 08:14:19PM +0100, Jozsef Kadlecsik wrote:
>> I think a single flag could be sufficient: if the timer in conntrack goes
>> off and the entry is in the ESTABLISHED state and this flag is not set,
>> then send a TCP keepalive packet and start the timer with a short timeout.
>> If we receive the reply packet, then the long ESTABLISHED timeout value
>> can be restored and the flag cleared.
> Sure, I think we wouldn't even need that flag, we can just send the keepalive
> and set a short timeout. If a RST is received, the connection is killed
> anyway, otherwise it will be refreshed with the ESTABLISHED timeout.
>
> But we do need a timestamp value to pass PAWS.
I believe you forgot the third scenario: neither ACK nor RST is received
in reply.
next prev parent reply other threads:[~2013-10-27 19:23 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-26 20:14 conntrack, idle TCP connection and keep-alives WGH
2013-10-27 15:34 ` Phil Oester
2013-10-27 18:01 ` Patrick McHardy
2013-10-27 18:38 ` Patrick McHardy
2013-10-27 19:14 ` Jozsef Kadlecsik
2013-10-27 19:20 ` Patrick McHardy
2013-10-27 19:23 ` WGH [this message]
2013-10-27 19:32 ` Patrick McHardy
2013-10-27 19:34 ` Patrick McHardy
2013-10-27 19:50 ` Jozsef Kadlecsik
2013-10-27 20:49 ` Jozsef Kadlecsik
2013-10-28 9:29 ` Patrick McHardy
2013-10-27 18:22 ` WGH
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