Re: [PATCH 0/3] Namespaceify tcp keepalive machinery

From: David Miller
Date: Sun Jan 10 2016 - 17:32:43 EST

From: Nikolay Borisov <kernel@xxxxxxxx>
Date: Thu, 7 Jan 2016 16:38:42 +0200

> The following patch series enables the tcp keepalive mechanism
> to be configured per net namespace. This is especially useful
> if you have multiple containers hosted on one node and one of
> them is under DoS- in such situations one thing which could
> be done is to configure the tcp keepalive settings such that
> connections for that particular container are being reset
> faster.
> Another scenario where not being able to control those knob
> comes per container is problematic is occurs the value of
> net.netfilter.nf_conntrack_tcp_timeout_established is set
> below the keepalive interval, in such situations the server won't
> send an RST packet resulting in applications not trying to
> reconnect and stale connection waiting. Changing the global
> keepalive value is a possible solution but it might interfere
> with other containers.
> The three patches gradually convert each of the affected knobs
> to be per netns. I thought it would be easier for review than
> put everything in one patch. If people deem it more appropriate
> to squash everything in one patch (maybe after review) I'd
> be more than happy to do it.
> The patches have been compile-tested on 4.4 and functionally
> tested on 3.12 and they work as expected.
> These are based off 4.4-rc8

Series applied, thanks.