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To: Proxmox VE development discussion <pve-devel@lists.proxmox.com>,
 Alexandre Derumier <aderumier@odiso.com>
References: <20201016132417.5175-1-m.limbeck@proxmox.com>
 <20201016132417.5175-3-m.limbeck@proxmox.com>
 <CAMGxVzBeP3j6CsF8SXnV8crdv15d3AC6_1MNrTQSdnB=82eEDQ@mail.gmail.com>
From: Thomas Lamprecht <t.lamprecht@proxmox.com>
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Date: Mon, 19 Oct 2020 07:46:38 +0200
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Subject: Re: [pve-devel] [PATCH qemu-server] copy conntrack information on
 migration
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On 17.10.20 17:42, Alexandre Derumier wrote:
> Hi,
> thanks for this patch !
>=20
> It could be interesting to see if it's working fine with
> sysctl -w net/netfilter/nf_conntrack_tcp_loose=3D0
>=20
> This is to avoid  ack flood ddos  (where random ack packets can add a
> lot of conntrack entries)
> https://2014.rmll.info/slides/356/day_1-1400-Jesper_Brouer-DDoS_protect=
ion_using_Netfilter_iptables.pdf
>=20
> Currently we can't enable it because  when we migrate vms, the already
> opened connected can't readd conntrack without a new syn.

That was the main intention for this series, i.e., your bug #2451 :)
https://bugzilla.proxmox.com/show_bug.cgi?id=3D2451