From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S968368AbdEWPOx (ORCPT ); Tue, 23 May 2017 11:14:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41090 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967218AbdEWPOt (ORCPT ); Tue, 23 May 2017 11:14:49 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 5E0904E35B Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=dhowells@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 5E0904E35B Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: <87zie3mxkc.fsf@xmission.com> References: <87zie3mxkc.fsf@xmission.com> <149547014649.10599.12025037906646164347.stgit@warthog.procyon.org.uk> <1495472039.2757.19.camel@HansenPartnership.com> <2446.1495551216@warthog.procyon.org.uk> To: ebiederm@xmission.com (Eric W. Biederman) Cc: dhowells@redhat.com, Aleksa Sarai , James Bottomley , trondmy@primarydata.com, mszeredi@redhat.com, linux-nfs@vger.kernel.org, jlayton@redhat.com, Linux Containers , linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org, cgroups@vger.kernel.org Subject: Re: [RFC][PATCH 0/9] Make containers kernel objects MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <2960.1495552481.1@warthog.procyon.org.uk> Date: Tue, 23 May 2017 16:14:41 +0100 Message-ID: <2961.1495552481@warthog.procyon.org.uk> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 23 May 2017 15:14:48 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Eric W. Biederman wrote: > > As an example, I could set up a client machine with two ethernet ports, > > set up two DNS+NFS servers, each of which think they're called "foo.bar" > > and attach each server to a different port on the client machine. Then I > > could create a pair of containers on the client machine and route the > > network in each container to a different port. Now there's a problem > > because the names of the cached DNS records for each port overlap. > > Please look at ip netns add. warthog>man ip | grep setns warthog1> > It does solve this in userspace rather simply. Ummm... How? The kernel DNS resolver is not namespace aware. David